Structural Design Logic of Common Resin Modification Technologies: Molecular Chain Structure, Functional Groups, Phase Structure, Crosslinked Networks, and Hybrid/Functional Design
Structural Design Logic of Common Resin Modification Technologies: Molecular Chain Structure, Functional Groups, Phase Structure, Crosslinked Networks, and Hybrid/Functional Design
1. Introduction: Resin Modification Technologies as Structural Engineering Tools
The same resin can be modified in different ways, and different resins can also achieve performance improvements through similar structural design strategies. For example, copolymerization can be used to adjust the glass transition temperature, Tg; grafting can improve the compatibility between different chain segments; core–shell structures can allow soft and hard phases to perform different functions; crosslinking can transform a linear resin into a three-dimensional network; and hybridization can introduce organic segments, inorganic structures, or functional groups into the same coating film system. Common resin modification technologies can be grouped into five categories.
Modification Level | Representative Technologies | Main Structural Changes | Main Properties Affected |
Molecular chain structure modification | Copolymerization, grafting, block structures, branching, hyperbranching | Segment composition, segment arrangement, molecular weight, degree of branching | Tg, hardness, flexibility, film-forming ability, viscosity |
Functional group modification | Hydroxyl, carboxyl, epoxy, silane, double bonds, phosphate groups | Reactive sites, polarity, interfacial interactions | Adhesion, reactivity, dispersion stability, functionalization capability |
Phase structure modification | Core–shell structures, gradient structures, microgels, IPN, semi-IPN | Soft/hard phase distribution, multiphase structures, interpenetrating networks | Film formation, blocking resistance, toughening, wear resistance, mechanical stability |
Crosslinked network modification | Self-crosslinking, two-component crosslinking, amino crosslinking, epoxy–amine curing, UV/EB curing | Crosslink density, degree of curing, three-dimensional network structure | Hardness, water resistance, solvent resistance, chemical resistance, heat resistance |
Hybrid and functional modification | Organic–organic hybridization, organic–inorganic hybridization, nanocomposites, low-surface-energy modification, dynamic structures | Functional segments, inorganic structures, surface structures, reversible structures | Weatherability, stain resistance, corrosion protection, heat resistance, self-healing, special functions |
These five categories are not completely independent from one another. In practical resin design, two or more modification methods are often used simultaneously. For example, a core–shell emulsion may involve copolymer design, functional group design, and post-crosslinking design at the same time. An organic–inorganic hybrid resin may involve silane functional groups, an inorganic network, and crosslinking of the organic resin simultaneously.
2. Molecular Chain Structure Modification: Adjusting the Basic Properties of Resins
Molecular chain structure modification is one of the most fundamental approaches in resin modification. By changing the composition of resin chain segments, segment arrangement, molecular weight, molecular weight distribution, and degree of branching, it can regulate Tg, hardness, flexibility, film-forming ability, weatherability, viscosity, and application properties. Molecular chain structure modification mainly includes copolymerization, grafting, block modification, introduction of flexible segments, introduction of rigid segments, branching, and hyperbranching modification.
2.1 Copolymerization Modification: Adjusting Properties Through Composition
Copolymerization modification refers to the joint polymerization of two or more monomers so that different structural units are incorporated into the same polymer chain. Its main function is to regulate the basic properties of the resin through monomer composition. Copolymerization modification is commonly used to adjust Tg, hardness, flexibility, polarity, water resistance, film-forming ability, and reactivity.
For example, in acrylic resins, increasing the proportion of hard monomers usually raises Tg, hardness, and blocking resistance. Increasing the proportion of soft monomers usually improves flexibility and low-temperature film formation. Introducing polar monomers can improve adhesion or dispersion stability, but excessive polar structures may increase water absorption.
Copolymer Design Direction | Main Function | Issues to Consider |
Increase the proportion of hard monomers | Increases Tg, hardness, and blocking resistance | Flexibility and low-temperature film formation decrease |
Increase the proportion of soft monomers | Improves flexibility, film-forming ability, and low-temperature performance | Hardness, heat resistance, and blocking resistance decrease |
Introduce polar monomers | Improves adhesion, dispersion, and reactivity | Water resistance may decrease |
Introduce hydrophobic monomers | Improves water resistance, stain resistance, and low water absorption | Dispersion stability may become poorer |
Introduce reactive monomers | Provides post-crosslinking or curing sites | Storage stability and reaction control requirements increase |
The advantages of copolymerization modification are its broad adjustment range, mature industrialization, and wide applicability. Its limitation is that different properties often constrain one another. Simply adjusting the monomer ratio is often insufficient to simultaneously meet requirements for hardness, flexibility, water resistance, and application performance.
2.2 Graft Modification: Improving Compatibility Through Chemical Connection
Graft modification refers to chemically attaching one type of chain segment to another polymer main chain or backbone. Compared with simple physical blending, grafted structures can improve the compatibility between different chain segments and reduce phase separation and performance instability. The main functions of graft modification include:
① Introducing the performance advantages of one structural unit into another resin;
② Improving compatibility between different polymers;
③ Enhancing coating film uniformity and mechanical stability;
④ Reducing delamination, haze, or adhesion loss caused by simple blending;
⑤ Forming a more stable structural connection between the main chain and side chains.
Function of Graft Modification | Significance for the Coating Film |
Improves chain-segment compatibility | Reduces phase separation and improves coating film uniformity |
Introduces functional side chains | Adds hydrophobicity, stain resistance, reactivity, or adhesion capability |
Adjusts main-chain flexibility | Improves impact resistance, bending performance, and low-temperature performance |
Improves interfacial bonding | Enhances substrate adhesion or intercoat adhesion |
The key factors in graft modification are grafting ratio, grafting position, grafted chain length, and reaction control. If the degree of grafting is too low, the modification effect will not be obvious. If the degree of grafting is too high, viscosity may increase, film formation may become difficult, or system stability may decrease.
2.3 Block Modification: Achieving Property Synergy Through Soft and Hard Segment Arrangement
Block modification refers to the formation of structurally distinct segments within the same polymer chain. Unlike random copolymerization, soft segments and hard segments in a block structure have relatively independent structural characteristics, making it easier to achieve synergy between soft and hard segments. The typical roles of block structures are as follows:
Block Structure | Main Contribution |
Soft segments | Flexibility, elasticity, low-temperature performance, energy dissipation capability |
Hard segments | Strength, hardness, wear resistance, heat resistance, blocking resistance |
Soft/hard segment ratio | Determines the soft–hard balance of the coating film |
Degree of phase separation | Affects transparency, mechanical properties, and film-forming uniformity |
The advantage of block modification is its strong structural designability. It is suitable for addressing problems that simple copolymerization cannot easily solve, such as balancing flexibility and strength. Its limitation is that synthesis control requirements are relatively high, and the compatibility and phase separation degree of the soft and hard segments must be properly controlled.
2.4 Branching and Hyperbranching Modification: Reducing Viscosity and Increasing Terminal Groups
As the molecular weight of a linear resin increases, chain entanglement becomes stronger, and system viscosity usually rises significantly. Branching and hyperbranching modification can reduce the degree of chain entanglement while maintaining a certain molecular weight and reactive functionality, thereby improving the application performance of high-solids systems. Hyperbranched resins have many terminal functional groups, lower molecular chain entanglement, and relatively low viscosity. Therefore, they are often used in the design of high-solids, low-VOC systems and fast-curing systems.
Structural Feature of Branching | Effect on Resin Properties |
Reduced molecular chain entanglement | Lowers viscosity and helps increase solids content |
More terminal groups | Increases reactivity and crosslinking points |
Compact molecular structure | Improves application performance and flow |
Higher functionality | May improve hardness and chemical resistance after curing |
Branching and hyperbranching modification also require control of functionality and curing rate. If the functionality is too high or curing is too fast, the coating film may develop shrinkage stress, increased brittleness, or insufficient leveling.
3. Functional Group Modification: Providing Resin Reactivity and Interfacial Interaction
Functional group modification refers to the introduction of specific reactive groups or polar groups into the resin structure, enabling the resin to have reactivity, adhesion, dispersion, coupling, or functionalization capability. Functional groups determine not only whether the resin can form a film, but also whether it can interact effectively with curing agents, substrates, pigments and fillers, or other resins.
3.1 Main Functions of Functional Groups
Functional group modification mainly addresses three types of issues.
Function Type | Specific Meaning | Significance for Coatings |
Provides reactivity | The resin can participate in curing, post-crosslinking, photocuring, or coupling reactions | Converts the resin from an ordinary film-forming material into a reactive material |
Provides interfacial interaction | The resin can interact with metals, plastics, glass, wood, mineral substrates, or pigments and fillers | Improves adhesion, wetting, and interfacial stability |
Provides functional entry points | The resin can introduce anticorrosion, flame-retardant, stain-resistant, hydrophobic, or self-healing structures | Provides reactive sites for special functional modification |
Introducing functional groups usually increases the design flexibility of a resin, but it also changes the resin’s polarity, water absorption, viscosity, storage stability, and reaction rate. Functional group modification requires control over the type, content, distribution, and reactivity of the groups.
3.2 Common Functional Groups and Their Roles
Functional Group | Main Function | Common Applications | Issues to Control |
Hydroxyl group | Provides reaction sites with isocyanates or amino resins | Two-component polyurethane, amino baking coatings, hydroxyl acrylic resins | Excessively high hydroxyl value may increase viscosity and water absorption |
Carboxyl group | Provides polarity, dispersion stability, and reactive sites | Waterborne dispersions, metal adhesion, carboxyl–epoxy reactions | Excessive content may affect water resistance and salt spray resistance |
Epoxy group | Improves adhesion, reactivity, and chemical-resistant structural design capability | Metal anticorrosion, epoxy modification, reactive adhesion promotion | Matching with curing agents and storage stability must be controlled |
Isocyanate group | Reacts with hydroxyl, amino, water, and other groups | Two-component polyurethane, moisture-curing systems | Sensitive to moisture; pot life must be controlled |
Silane group | Undergoes hydrolysis–condensation or coupling and improves interfacial bonding with inorganic substrates | Glass, metal, mineral substrates, silane-modified resins | Premature hydrolysis may cause gelation or storage instability |
Acrylate double bond | Participates in UV or EB curing | UV/EB-curable coatings, fast-curing topcoats | Oxygen inhibition, shrinkage stress, and deep curing must be controlled |
Phosphate group | Enhances metal interfacial interaction and supports anticorrosion design | Metal primers, anticorrosive coatings, adhesion promotion | Acidity, compatibility, and water resistance must be balanced |
Fluorinated or silicon-containing groups | Provide low surface energy, hydrophobicity, or stain-resistant functional entry points | Stain-resistant, hydrophobic, easy-clean coatings | Excessive surface enrichment may affect recoating and intercoat adhesion |
3.3 Effects of Functional Group Content and Distribution on Properties
For functional groups, the type of group is not the only important factor; content and distribution also matter. Chain-end distribution, side-chain distribution, surface enrichment, and local enrichment can all affect reaction efficiency, interfacial interaction, water resistance, and compatibility.
Distribution Mode of Functional Groups | Possible Effects |
Uniform distribution | More uniform reaction and more stable coating film properties |
Chain-end enrichment | High reaction efficiency; suitable for terminal-group curing design |
Side-chain distribution | Facilitates adjustment of polarity, adhesion, and reactivity |
Surface enrichment | Beneficial for surface hydrophobicity, stain resistance, or slip |
Excessive local enrichment | May cause phase separation, water-absorbing sites, or brittle regions |
For example, moderate enrichment of silicon or fluorine structures on the coating film surface can improve hydrophobicity and stain resistance. However, excessive migration may affect intercoat adhesion. Carboxyl groups are beneficial for dispersion and adhesion, but if too many hydrophilic sites remain in the coating film, water resistance may decrease.
4. Phase Structure Modification: Using Multiphase Structures to Assign Different Functions
Phase structure modification focuses on the spatial distribution and functional division of different phases or networks within the resin system. Its focus is not the crosslinking reaction itself, but rather the difficulty of using a single homogeneous resin to simultaneously satisfy requirements such as hardness, flexibility, low-temperature film formation, blocking resistance, wear resistance, and impact resistance.
Phase structure modification mainly includes core–shell structures, gradient structures, microgel structures, interpenetrating polymer networks, IPN, and semi-interpenetrating polymer networks, semi-IPN.
4.1 Core–Shell Structures: Allowing Different Phases to Perform Different Functions
A core–shell structure usually consists of an inner core and an outer shell. The core and shell may have different Tg values, different polarities, different degrees of crosslinking, or different functional groups.
Core–Shell Type | Main Function |
Soft core / hard shell | The soft core provides film formation and flexibility, while the hard shell provides hardness and blocking resistance |
Hard core / soft shell | The hard core provides strength and dimensional stability, while the soft shell improves film formation and adhesion |
Functional shell layer | The shell layer provides water resistance, adhesion, surface functionality, or reactive sites |
Crosslinked core structure | Provides dimensional stability, solvent resistance, and deformation resistance |
Gradient core–shell structure | Relieves differences between soft and hard phases and reduces phase separation and internal stress |
The value of core–shell structures lies in allowing different regions to perform different functions. For example, low-temperature film formation usually requires a lower Tg or higher segmental mobility, whereas blocking resistance and hardness usually require a higher Tg or higher degree of crosslinking. Core–shell structures can alleviate this conflict to some extent.
The minimum film-forming temperature, MFFT, is an important indicator for evaluating whether a dispersion-type resin can form a continuous coating film at a given temperature. The particle size, shell composition, and soft/hard phase distribution of core–shell particles can all affect MFFT and the final coating film properties. At the same time, MFFT is also influenced by factors such as coalescing agents, emulsion formulation, particle size distribution, drying conditions, and testing conditions.
4.2 Gradient Structures: Reducing Abrupt Property Changes and Internal Stress Concentration
A gradient structure refers to a resin particle or coating film microdomain in which composition, Tg, degree of crosslinking, or polarity changes gradually from one region to another. Compared with a clearly layered core–shell structure, a gradient structure can reduce abrupt transitions between soft and hard phases. Gradient structures are suitable for systems that need to balance film formation, blocking resistance, flexibility, and durability, but their synthesis process and structural characterization requirements are relatively high.
Structure Type | Characteristics | Main Application Focus |
Clear core–shell structure | Clear functional division between soft and hard phases; obvious property differences | Balance between film formation and blocking resistance |
Gradient structure | Composition changes gradually; internal stress is easier to relieve | Flexibility, film-forming continuity, and mechanical stability |
Homogeneous structure | Simple structure, but limited functional division capability | Systems with ordinary performance requirements |
4.3 Microgel Structures: Introducing Local Crosslinked Microdomains into the System
Microgels are polymer particles or microdomains with a certain crosslinked structure. They can serve as local reinforcing structures and can also be used to regulate rheology and improve the mechanical stability of the coating film. The main functions of microgel structures include:
① Providing local reinforcement;
② Improving sag resistance;
③ Regulating coating film shrinkage and internal stress;
④ Improving solvent resistance;
⑤ Improving mechanical stability.
The size, degree of crosslinking, and compatibility of microgels with the continuous phase must be controlled. If the microgels are poorly dispersed, they may cause surface roughness, reduced transparency, or coating film defects.
4.4 IPN and semi-IPN: Improving Overall Performance Through Interpenetrating Networks
An IPN refers to two or more polymer networks that are at least partially interpenetrated at the molecular scale. The networks are usually not connected by covalent bonds, and they are difficult to separate from each other unless chemical bonds are broken. In a semi-IPN, usually only one polymer forms a crosslinked network, while another linear or branched polymer chain penetrates that network.
Structure Type | Structural Characteristics | Main Function |
IPN | Two or more networks interpenetrate each other | Improves mechanical strength, chemical resistance, and toughening effect |
semi-IPN | One network coexists with a linear or branched polymer | Improves flexibility, application performance, and overall performance |
Simple blend | Different resins are physically blended | Easily affected by compatibility |
IPN design requires attention to two points: ① whether the formation rates of the two networks match; ② whether severe phase separation occurs between the two polymers. If the reaction rates differ too much, the structure may become nonuniform. If compatibility is insufficient, haze, reduced mechanical properties, or coating film defects may occur.
5. Crosslinked Network Modification: From Linear Film Formation to a Three-Dimensional Network
Crosslinked network modification focuses on the three-dimensional network structure formed after the resin has formed a film. It differs from phase structure modification: phase structure focuses on the spatial distribution and functional division of different phases, while crosslinked network modification focuses on crosslink density, degree of curing, network uniformity, and network flexibility. Linear resins mainly rely on chain entanglement and physical interactions for film formation. In contrast, crosslinked resins form a three-dimensional network after curing and, when curing is sufficient, the network is uniform, and hydrophilic groups and microdefects are controlled, they can usually significantly improve the water resistance, solvent resistance, chemical resistance, hardness, and heat resistance of the coating film.
5.1 Which Properties Are Affected by the Crosslinked Network?
Crosslinked Network Factor | Effect on Properties |
Crosslink density | Affects hardness, solvent resistance, water resistance, and chemical resistance |
Network uniformity | Affects toughness, cracking risk, and durability |
Degree of curing reaction | Affects early-stage properties and final properties |
Network flexibility | Affects bending, impact resistance, and internal stress |
Reaction rate | Affects leveling, application time, and curing efficiency |
5.2 Common Crosslinking Modification Methods
Crosslinking Method | Main Reaction Characteristics | Common Applications | Issues to Control |
Self-crosslinking | The resin crosslinks by itself after film formation | Waterborne resins, low-temperature curing systems | Storage stability and degree of post-crosslinking |
Two-component crosslinking | Main component and curing agent react after mixing | Two-component polyurethane, two-component epoxy | Pot life, mixing ratio, application time |
Amino crosslinking | Hydroxyl resin and amino resin undergo thermal curing | Baking coatings, industrial coatings, automotive coatings | Baking conditions, acid catalysis, flexibility |
Epoxy–amine curing | Epoxy groups react with amine curing agents | Anticorrosive coatings, flooring, structural coatings | Curing rate, low-temperature curing, brittleness |
Silane condensation | Silane hydrolyzes and then condenses into a siloxane network | Adhesion to inorganic substrates, water-resistance modification | Humidity, pH, storage stability |
UV/EB curing | Double bonds polymerize rapidly under ultraviolet light or electron beam irradiation | Wood coatings, plastic coatings, electronics, packaging coatings | Oxygen inhibition, insufficient UV shadow/deep curing, EB inert atmosphere and equipment control, shrinkage stress |
Dual curing | Two curing mechanisms work synergistically | Thick coatings, complex structures, functional coatings | Matching of reaction sequence and degree of curing |
UV/EB curing is a highly reactive crosslinking method and is commonly used in fast-curing and low-VOC systems. Its advantages include fast curing and high production efficiency. Issues that need to be controlled include oxygen inhibition, curing shrinkage, insufficient curing in thick films or shadowed regions, and reduced adhesion. Unlike UV curing, EB curing usually does not rely on photoinitiators.
5.3 Main Risks of Crosslinking Modification
The most common issue in crosslinking modification is overemphasizing water resistance, solvent resistance, and hardness while neglecting coating film toughness, adhesion, and application time. A reasonable crosslinking design should balance durability, toughness, adhesion, and application performance.
Improper Crosslinking Design | Possible Result |
Crosslink density too low | Insufficient solvent resistance, water resistance, and hardness |
Crosslink density too high | Increased brittleness, reduced impact resistance, higher cracking risk |
Curing too fast | Insufficient leveling, orange peel, increased internal stress |
Insufficient curing | Poor early-stage performance and insufficient chemical resistance |
Nonuniform network | Local brittleness, local swelling, or coating film defects |
6. Hybrid and Functional Modification: Introducing Special Structural Units
Hybrid and functional modification refers to introducing different types of structural units into a resin system so that it can obtain comprehensive properties or special functions that a single resin would have difficulty achieving. It includes not only hybridization between organic resins, but also organic–inorganic hybridization, nanocomposites, low-surface-energy modification, and the introduction of dynamic chemical structures.
6.1 Organic–Organic Hybridization: Complementary Properties of Different Chain Segments
Organic–organic hybridization refers to the formation of combined structures between different organic resin structures through grafting, block structures, interpenetrating networks, reactive compounding, or other chemical methods. Its core purpose is to allow different chain segments in the same system to perform different functions. For example, one type of structure may be responsible for adhesion and corrosion protection, while another structure may be responsible for flexibility, weatherability, or wear resistance.
Key Issue in Organic–Organic Hybridization | Explanation |
Compatibility | Determines whether delamination, haze, or mechanical property loss occurs |
Chemical connection method | Determines whether the hybrid structure is stable |
Reaction matching | Determines whether the curing process is uniform |
Soft–hard balance | Determines hardness, flexibility, and impact resistance |
Application adaptability | Determines viscosity, open time, and leveling |
The value of organic–organic hybridization lies in property complementarity. Its risks include insufficient compatibility, mismatched reaction rates, and reduced application stability. Compared with simple blending, grafting, block structures, IPN, or reactive hybridization is usually more favorable for forming a stable structure.
6.2 Organic–Inorganic Hybridization and Nanocomposites: Reinforcement, Barrier Effects, and Heat Resistance
Organic–inorganic hybridization refers to the introduction of inorganic structures such as siloxanes, metal oxides, nano-silica, nano-alumina, montmorillonite, and graphene-like sheets into organic resins. Nanocomposite modification can also usually be discussed under this category. Strictly speaking, however, organic–inorganic hybridization places greater emphasis on chemical connection, sol–gel reactions, or strong interfacial interactions between the organic phase and the inorganic phase, whereas nanocomposites may simply involve the dispersion and interfacial modification of nanofillers in an organic resin.
The main purposes of organic–inorganic hybridization and nanocomposites include increasing hardness, improving wear resistance, improving heat resistance, enhancing anticorrosive barrier performance, improving dimensional stability, and introducing special functions such as electrical conductivity, antistatic performance, and flame retardancy.
Inorganic or Nanoscale Structure | Main Contribution | Issues to Control |
Silica | Hardness, wear resistance, heat resistance, transparent reinforcement | Dispersion, compatibility, brittleness |
Alumina | Wear resistance, hardness, heat resistance | Transparency and surface roughness |
Montmorillonite | Lamellar barrier effect, corrosion protection, reinforcement | Degree of exfoliation and dispersion stability |
Graphene-like sheets | Barrier effect, corrosion protection, electrical conductivity, or antistatic performance | Agglomeration, cost, and dispersion difficulty |
Siloxane network | Water resistance, heat resistance, weatherability, and adhesion | Control of hydrolysis and condensation |
The key to organic–inorganic hybridization and nanocomposites is not that the higher the inorganic material loading, the better the result. Rather, the key is whether the inorganic phase can be uniformly dispersed and form a stable interface with the organic resin. If interfacial bonding is poor, nanoscale or inorganic structures may become defect sources, leading to coating film roughness, reduced transparency, decreased water resistance, or unstable anticorrosive performance. For systems using conductive sheets such as graphene for metal corrosion protection, it is also necessary to control sheet dispersion, defects, and continuous conductive pathways. If the coating film contains pinholes, cracks, or scratches, there may be a risk of localized galvanic corrosion.
6.3 Surface Functionalization: Low Surface Energy, Hydrophobicity, and Stain Resistance
Surface functionalization refers to the use of fluorinated, silicon-containing, or other low-surface-energy structures to give the coating film surface properties such as hydrophobicity, stain resistance, slip, easy cleaning, or resistance to pollutant adhesion. The main functions of low-surface-energy structures include:
① Reducing wetting by water and pollutants;
② Improving surface stain resistance;
③ Improving slip and tactile feel;
④ Reducing the adhesion strength of pollutants;
⑤ Improving the self-cleaning or clean-retention performance of certain outdoor coatings.
However, low-surface-energy structures may also bring problems.
Modification Effect | Potential Issue |
Improved surface hydrophobicity | May affect wetting during recoating |
Improved stain resistance | Intercoat adhesion may decrease |
Improved surface slip | Subsequent coating or printing adaptability may become poorer |
Strong surface enrichment | May cause cratering, leveling abnormalities, or compatibility issues |
6.4 Dynamic Functionalization: Self-Healing and Damage Response
Traditional coating films mainly rely on barrier effects, adhesion, and crosslinked networks for protection. When a coating film is scratched, cracked, or locally damaged, its protective performance decreases significantly. Dynamic functionalization attempts to provide the coating film with a certain degree of recovery after damage through reversible chemical bonds, physical interactions, or release of healing agents. Common designs include reversible covalent bonds, hydrogen bonds, metal coordination bonds, disulfide exchange, Diels–Alder reversible reactions, microcapsule healing agents, and corrosion-inhibitor nanocontainers.
The focus of these structures is to improve the durability of the coating film after damage. Their practical application must consider healing efficiency, triggering conditions, mechanical properties, cost, and long-term stability.
7. Comparison and Summary of Common Modification Technologies
Modification Tec hnology | Main Object Modified | Main Function | Key Control Points |
Copolymerization modification | Monomer composition and chain segment structure | Adjusts Tg, hardness, flexibility, and polarity | Monomer ratio, reactivity, molecular weight |
Graft modification | Connection between main chain and side chains | Improves compatibility and introduces functional segments | Grafting ratio, grafting position, chain segment length |
Block modification | Arrangement of soft and hard segments | Enables synergy between soft and hard properties | Soft/hard segment ratio, degree of phase separation |
Branching modification | Molecular architecture and number of terminal groups | Reduces viscosity, increases solids content and reactive sites | Degree of branching, functionality, curing shrinkage |
Functional group modification | Reactive groups and polar groups | Improves reactivity, adhesion, and functionalization capability | Group content, distribution, reactivity |
Core–shell structure | Soft/hard phases inside particles | Balances film formation, hardness, and blocking resistance | Core–shell ratio, shell Tg, particle size |
Gradient structure | Phase structure with gradual changes in composition or properties | Relieves internal stress and improves soft–hard transition | Gradient distribution, compatibility, synthesis control |
Microgel structure | Local crosslinked microdomains | Reinforcement, rheology control, auxiliary solvent resistance | Particle size, degree of crosslinking, dispersion state |
IPN/semi-IPN | Interpenetrating multi-network structure | Improves strength, toughness, and chemical resistance | Reaction rate, compatibility, network uniformity |
Crosslinking modification | Three-dimensional network | Improves water resistance, solvent resistance, hardness, and chemical resistance | Crosslink density, degree of curing, internal stress |
Organic–organic hybridization | Combination of different organic segments | Complementary properties | Compatibility, reaction matching, soft–hard balance |
Organic–inorganic hybridization / nanocomposites | Combination of inorganic phases or nanofillers with organic resins | Improves wear resistance, heat resistance, corrosion protection, and barrier performance | Dispersion, interfacial bonding, defects and brittleness |
Surface functionalization | Surface functional structures | Improves hydrophobicity, stain resistance, and slip | Surface enrichment, recoatability, compatibility |
Dynamic functionalization | Reversible structures or healing structures | Self-healing, damage response, improved durability | Triggering conditions, healing efficiency, long-term stability |
8. Representative Chemicals Related to Common Resin Modification Technologies
Table 1. Monomers Related to Copolymerization, Grafting, and Chain Segment Structure Control
Category | CAS No. | Aladdin Cat. No. | Name | Specification or Purity | Product Features and Applications |
Hydroxyl-functional monomer | 868-77-9 | 2-Hydroxyethyl methacrylate (HEMA) | Anhydrous grade, ≥99%, contains 200 ppm MEHQ as stabilizer, water ≤0.1% | Used for hydroxyl acrylic resins, reactive copolymers, and post-crosslinkable resin design; introduces hydroxyl reactive sites | |
Carboxyl-functional monomer | 79-10-7 | Acrylic acid | Anhydrous grade, ≥99%, contains 200 ppm MEHQ as stabilizer | Used for acrylic copolymerization, emulsion polymerization, and water-dispersible systems; introduces carboxyl groups and adjusts polarity and adhesion | |
Carboxyl-functional monomer | 79-41-4 | Methacrylic acid | Suitable for synthesis, stabilized with hydroquinone monomethyl ether | Used for methacrylic copolymer resins; improves polarity, adhesion, and reaction-control capability | |
Soft monomer | 141-32-2 | Butyl acrylate (BA) | Chemically pure (CP), ≥98%, contains 50 ppm MEHQ as stabilizer | Used for soft-segment copolymerization, low-temperature film formation, and flexibility adjustment; a commonly used monomer for soft–hard monomer balance design | |
Hard monomer | 100-42-5 | Styrene | CP, contains 10–15 ppm 4-tert-butylcatechol as stabilizer | Used for styrene-acrylic emulsions and hard-segment copolymer design; improves hardness, rigidity, and blocking resistance | |
Hard monomer | 80-62-6 | Methyl methacrylate (MMA) | AR, ≥99%, contains 30 ppm DMBP as stabilizer | Used for high-glass-transition-temperature acrylic resins, hard phases in core–shell systems, and weather-resistant copolymer design | |
Rigid hydrophobic monomer | 7534-94-3 | Isobornyl methacrylate | Contains 50–150 ppm MEHQ as stabilizer | Used to improve resin rigidity, heat resistance, water resistance, and the design of low-volatility reactive diluent systems | |
Hydrophobic monomer | 97-88-1 | Butyl methacrylate (BMA) | ≥99%, contains MEHQ as stabilizer | Used for hydrophobic acrylic copolymers and soft–hard balanced resin design; adjusts film-forming ability, water resistance, and flexibility | |
Amino-functional monomer | 2867-47-2 | 2-(Dimethylamino)ethyl methacrylate (DMAEMA) | ≥99%, contains 1000 ppm MEHQ as inhibitor | Used for cationic or reactive acrylic copolymers; introduces tertiary amine groups and improves dispersion and interfacial interactions | |
Soft monomer | 103-11-7 | 2-Ethylhexyl acrylate (2-EHA) | ≥99% (GC), contains 10–1100 ppm MEHQ as stabilizer | Used for low-glass-transition-temperature copolymers, flexible segments, and pressure-sensitive adhesive resin research | |
Sulfonic acid-functional monomer | 15214-89-8 | 2-Acrylamido-2-methyl-1-propanesulfonic acid (AMPS) | ≥98% | Used to introduce sulfonic acid groups and improve water-dispersion stability, ionicity, and emulsion polymerization stability design | |
Epoxy-functional monomer | 106-91-2 | Glycidyl methacrylate | ≥97%, contains 100 ppm MEHQ as stabilizer | Used for epoxy-functionalized acrylic resins, grafting reactions, and adhesion-promoting copolymer design | |
Hydroxyl-functional monomer | 27813-02-1 | Hydroxypropyl methacrylate (HPMA) | ≥97%, contains 0.02% 4-methoxyphenol as stabilizer | Used for hydroxyl acrylic resins, two-component curing systems, and reactive chain-segment modification research | |
Acetoacetyl-functional monomer | 21282-97-3 | Acetoacetoxyethyl methacrylate (AAEM) | ≥94%, contains 300 ppm BHT as stabilizer | Used for self-crosslinking emulsions, active carbonyl copolymers, and room-temperature post-crosslinking system design | |
Sulfonate-functional monomer | 2695-37-6 | Sodium 4-styrenesulfonate | ≥90% (T) | Used to introduce sulfonate structures; suitable for ionic copolymers, water-dispersible resins, and functional emulsion research |
Table 2. Products Related to Silane Coupling, Silicone Hybridization, and Fluorine Modification
Category | CAS No. | Aladdin Cat. No. | Name | Specification or Purity | Product Features and Applications |
Organic–inorganic hybrid precursor | 78-10-4 | Tetraethyl orthosilicate | Reagent grade, ≥98% | Used for sol–gel hybridization, siloxane network construction, and organic–inorganic composite coating research | |
Fluorinated modification monomer | 352-87-4 | 2,2,2-Trifluoroethyl methacrylate (TFEMA) | PrimorTrace™ Ultra, electronic grade, ≥99.9999% metals basis | Used for fluorinated acrylic resins, low-surface-energy copolymers, and stain-resistant surface functionalization research | |
Aminosilane coupling agent | 919-30-2 | 3-Aminopropyltriethoxysilane (APTS) | ≥99% | Used for adhesion to inorganic substrates, surface treatment of pigments and fillers, and interfacial coupling between resins and inorganic phases | |
Vinyl silane monomer | 2768-02-7 | Vinyltrimethoxysilane | ≥98% (GC) | Used for silane grafting, moisture-curing resins, and water-resistant hybrid polymer design | |
Siloxane network precursor | 1185-55-3 | Methyltrimethoxysilane | ≥98% | Used for siloxane networks, hydrophobic hybrid coatings, and sol–gel resin modification research | |
Methacryloxy silane | 2530-85-0 | 3-(Methacryloxy)propyltrimethoxysilane | ≥97%, contains 100 ppm BHT as stabilizer | Used for silane copolymerization of acrylic resins, grafting onto inorganic surfaces, and organic–inorganic interface modification | |
Epoxy silane coupling agent | 2530-83-8 | 3-Glycidyloxypropyltrimethoxysilane | ≥97% | Used for epoxy-functional silane modification, adhesion promotion on metal and inorganic substrates, and interfacial bonding in hybrid coatings | |
Vinyl silane monomer | 78-08-0 | Vinyltriethoxysilane (TEVS) | ≥97% | Used for silane graft copolymerization, water-resistant resin modification, and moisture-curing silicone hybrid systems | |
Fluorinated modification monomer | 36405-47-7 | 2,2,3,4,4,4-Hexafluorobutyl methacrylate (HFBMA) | ≥96%, contains MEHQ as stabilizer | Used for fluorinated acrylic resins, hydrophobic and stain-resistant coatings, and surface low-energy copolymer research |
Table 3. Products Related to Crosslinking/Curing, Reactive Resins, and Catalysis
Category | CAS No. | Aladdin Cat. No. | Name | Specification or Purity | Product Features and Applications |
Amino resin precursor | 108-78-1 | 2,4,6-Triamino-1,3,5-triazine | Suitable for synthesis | Used as a melamine/amino resin precursor, for triazine resin structures, and for thermally cured coating resin research | |
Aliphatic diisocyanate | 822-06-0 | Hexamethylene diisocyanate (HDI) | Moligand™, ≥99% | Used for polyurethane crosslinking, two-component coating curing agents, and weather-resistant polyurethane resin design | |
Basic raw material for epoxy resin | 1675-54-3 | Bisphenol A diglycidyl ether (BADGE) | Moligand™, ≥85% | Used for epoxy resins, anticorrosive coatings, epoxy-modified resins, and epoxy–amine curing systems | |
Hydrazide crosslinker | 1071-93-8 | Adipic dihydrazide (ADH) | ≥99% (HPLC) | Used for post-crosslinking of diacetone acrylamide copolymers, self-crosslinking emulsions, and room-temperature crosslinking systems | |
Amine curing agent | 111-40-0 | Diethylenetriamine | ≥99% | Used for epoxy resin curing, amine-reactive modification, and experimental systems for anticorrosive coatings | |
Carbonyl-crosslinking functional monomer | 2873-97-4 | Diacetone acrylamide (DAAM) | ≥99% | Used for self-crosslinking acrylic emulsions; works with hydrazide crosslinkers to construct room-temperature crosslinked networks | |
Alicyclic diisocyanate | 4098-71-9 | Isophorone diisocyanate, mixture of isomers (IPDI) | ≥99% | Used for polyurethane modification, weather-resistant polyurethane resins, and two-component crosslinking systems | |
Alicyclic diamine curing agent | 2855-13-2 | Isophorone diamine, cis/trans mixture (IPDA) | ≥99% | Used for epoxy curing, alicyclic amine curing systems, and chemical-resistant coating research | |
Amino crosslinker | 3089-11-0 | 2,4,6-Tris[bis(methoxymethyl)amino]-1,3,5-triazine | ≥98% (HPLC) | Used for thermal curing of hydroxyl resins, amino baking coating crosslinking, and chemical-resistant coating systems | |
Acid catalyst | 104-15-4 | p-Toluenesulfonic acid | ≥98% | Used for amino resin curing catalysis, esterification reactions, and acid-catalyzed crosslinking experiments | |
Reactive epoxy diluent | 2425-79-8 | 1,4-Butanediol diglycidyl ether (BDDE) | ≥95% | Used for viscosity reduction in epoxy systems, introduction of flexible segments, and reactive diluent modification | |
Polyurethane catalyst | 77-58-7 | Dibutyltin dilaurate (DBTDL) | ≥95% | Used for polyurethane reaction catalysis, isocyanate–hydroxyl reactions, and two-component curing research | |
Alicyclic diisocyanate | 5124-30-1 | Dicyclohexylmethane 4,4'-diisocyanate, mixture of isomers (HMDI) | ≥90% (GC) | Used for weather-resistant polyurethane resins, alicyclic polyurethane crosslinking, and high-performance coating modification | |
Reactive epoxy diluent | 17557-23-2 | Neopentyl glycol diglycidyl ether | ≥40% (GC) | Used for viscosity reduction in epoxy systems, reactive dilution, and flexibility adjustment of crosslinked networks |
Table 4. Products Related to UV Photoinitiators and UV/EB Reactive Diluents
Category | CAS No. | Aladdin Cat. No. | Name | Specification or Purity | Product Features and Applications |
Photoinitiator | 947-19-3 | 1-Hydroxycyclohexyl phenyl ketone | ≥98% | Used for ultraviolet-curable coatings, photopolymerization of acrylate systems, and fast-curing experiments | |
Photoinitiator | 7473-98-5 | 2-Hydroxy-2-methylpropiophenone | ≥97% | Used for free-radical photocuring systems, transparent coatings, and acrylate monomer polymerization | |
Acylphosphine oxide photoinitiator | 75980-60-8 | Diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide | ≥97% | Used for ultraviolet curing, thick-film curing, and free-radical photopolymerization research in pigmented systems | |
Acylphosphine oxide photoinitiator | 162881-26-7 | Phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (BAPO) | ≥97% | Used for UV-curable coatings, deep curing, and highly reactive acrylate systems | |
Difunctional acrylate | 42978-66-5 | Tripropylene glycol diacrylate | ≥90%, total of isomers, stabilized with MEHQ | Used for photocurable reactive dilution, crosslink density adjustment, and flexible UV-curable systems | |
Difunctional acrylate | 13048-33-4 | 1,6-Hexanediol diacrylate (HDDA) | ≥90%, contains MEHQ as stabilizer | Used for UV-curable coatings, construction of crosslinked networks, and low-viscosity reactive diluent systems | |
Trifunctional acrylate | 15625-89-5 | Trimethylolpropane triacrylate | ≥85%, contains 600 ppm MEHQ as stabilizer | Used for high-crosslink-density UV-curable systems, hardness improvement, and fast-curing coating research |
Table 5. Products Related to Nano-Reinforcement, Barrier Fillers, and Dynamic Functionalization
Category | CAS No. | Aladdin Cat. No. | Name | Specification or Purity | Product Features and Applications |
Carbon-based barrier material | 1034343-98-0 | G302114 | Graphene | High purity, ≥98% | Used for nanocomposite coatings, anticorrosive barrier coatings, conductive coatings, and resin reinforcement research |
Layered inorganic material | 1318-93-0 | M758183 | Montmorillonite K-10 | Powder | Used for lamellar barrier effects, anticorrosive coatings, nanocomposite resins, and organic–inorganic hybrid research |
Inorganic reinforcing filler | 1344-28-1 | Alumina | ≥99.9% metals basis | Used for wear resistance, hardness improvement, inorganic reinforcement, and high-performance composite coating research | |
Nano-inorganic reinforcing material | 7631-86-9 | Nano-silica | ≥99.5% metals basis, 30 nm | Used for nano-reinforcement, wear and scratch resistance, transparent reinforcement, and organic–inorganic hybrid coatings | |
Dynamic functionalization monomer | 98-00-0 | Furfuryl alcohol | AR, ≥98% | Used for furan-functional structures, reversible reaction modification, and self-healing resin research | |
Dynamic functionalization monomer | 541-59-3 | Maleimide | ≥98% | Used for reversible addition reactions, dynamic crosslinked structures, and self-healing polymer systems |
Note: The above are representative Aladdin products. For more product specifications, search by “product name / CAS / catalog number” on the Aladdin official website.
References
[1] Wicks Z. W., Jones F. N., Pappas S. P., Wicks D. A. Organic Coatings: Science and Technology, 3rd ed. Wiley-Interscience, 2007.
[2] Lambourne R., Strivens T. A. Paint and Surface Coatings: Theory and Practice, 2nd ed. Woodhead Publishing, 1999.
[3] Pieters K., Mekonnen T. H. Progress in waterborne polymer dispersions for coating applications: commercialized systems and new trends. RSC Sustainability, 2024.
[4] Jikei M., Kakimoto M. Hyperbranched polymers: a promising new class of materials. Progress in Polymer Science, 2001, 26(8): 1233–1285.
[5] Cook W. D., et al. Educational series: characterizing crosslinked polymer networks. Polymer Chemistry, 2024.
[6] SpecialChem. MFFT (Minimum Film Forming Temperature): Process & Test Methods.
[7] Sperry P. R., Snyder B. S., O’Dowd M. L., Lesko P. M. Role of water in particle deformation and compaction in latex film formation. Langmuir, 1994, 10(8): 2619–2628.
[8] Kausar A. Polyurethane/Epoxy Interpenetrating Polymer Network. In: Aspects of Polyurethanes. IntechOpen, 2017.
[9] Pathania A., Arya R. K., Ahuja S. Crosslinked polymeric coatings: Preparation, characterization, and diffusion studies. Progress in Organic Coatings, 2017. DOI: 10.1016/j.porgcoat.2016.12.023.
[10] Decker C. Kinetic study and new applications of UV radiation curing. Macromolecular Rapid Communications, 2002, 23(18): 1067–1093.
[11] Ghosh S. K. UV and EB Curing Technology and Equipment. Wiley, 1998.
[12] Figueira R. B., Silva C. J. R., Pereira E. V. Hybrid sol–gel coatings for corrosion mitigation: a critical review. Polymers, 2020, 12(3): 689.
[13] Montemor M. F. Functional and smart coatings for corrosion protection: a review of recent advances. Surface and Coatings Technology, 2014, 258: 17–37.
More related articles are listed below:
Understanding Amine Curing Agents: Structure, Types, and Application Selection
Epoxy Resin: From Reactive Resin to High-Performance Material System
