1. Solve Incompatibility Between Hydrophilic Quartz and Hydrophobic Epoxy Resin
Raw quartz powder has massive silanol (-OH) groups on its surface, which are highly hydrophilic. Epoxy resin is an organic hydrophobic polymer.
- Unmodified quartz tends to cluster and agglomerate when mixed with epoxy, forming tiny voids inside cured epoxy products.
- The inorganic-organic interface only has weak physical adsorption instead of chemical bonding, leading to poor composite integrity.
Surface modification grafts organic molecular chains onto quartz surfaces, turning hydrophilic powder into hydrophobic filler that can uniformly blend with epoxy resin matrix.
2. Strengthen Interfacial Bonding & Boost Mechanical Properties of Epoxy Composites
Silane coupling agents used in modification contain dual reactive groups:
- One end reacts with quartz’s surface hydroxyl groups to form stable Si-O-Si covalent bonds, firmly attaching organic layers on quartz particles.
- The other end carries epoxy-reactive groups (glycidyl, amino groups) that cross-link chemically with epoxy resin during curing.
This creates a tight “chemical bridge” between quartz filler and epoxy matrix:
- Transfers stress evenly when the material bears external force
- Greatly improves flexural strength, tensile strength and impact resistance of epoxy products
- Avoids brittle cracking, peeling and delamination defects of pure epoxy or unmodified quartz-filled epoxy
3. Improve Powder Flowability & Enable High Filling Ratio in Epoxy
Unmodified quartz absorbs water easily and agglomerates severely, which limits its maximum filling proportion in epoxy (usually below 50wt%).
Modified quartz has smooth organic coating on particle surfaces:
- Reduces inter-particle friction and stacking resistance
- Supports ultra-high filling dosage up to 70–90wt% without sharp viscosity surge of epoxy slurry
- Lowers thermal expansion coefficient and curing shrinkage of epoxy, critical for electronic packaging epoxy molding compounds (EMC)
4. Eliminate Defects & Optimize Thermal, Insulation Performance
- Reduce water absorption: Bare silanol groups easily absorb moisture, which causes bubbling, insulation failure and yellowing of electronic epoxy after long-term use. Modified quartz’s organic barrier blocks water penetration and stabilizes dielectric properties.
- Uniform heat conduction: Well-dispersed modified quartz forms continuous heat conduction channels inside epoxy, lowering material thermal resistance for high-power electronic devices.
- Zero metal contamination matching: Combined with JACAN’s all-ceramic grinding pretreatment, modified high-purity quartz keeps metal impurities at ppm levels, maintaining high insulation for semiconductor packaging.
5. Optimize Processing Performance for Mass Production
- Lower melt viscosity of epoxy composite, better mold filling ability and fewer air bubbles during casting/compression molding.
- Less equipment wear: Lubricating organic coating reduces abrasion to mixers, extruders and molds.
- Stable batch consistency: Modified quartz avoids uneven agglomeration, ensuring uniform color, hardness and dimensional stability of finished epoxy parts.
6. Expand Application Range of Quartz Powder in Epoxy Products
Without surface modification, quartz can only be used in low-end ordinary epoxy coatings. After functional modification with targeted silane agents:
- KH-560 modified quartz: High-end electronic packaging epoxy, semiconductor plastic packaging materials
- Amino silane modified quartz: Low-temperature curing epoxy adhesives, structural composite glues
- Phenyl silane modified quartz: High-frequency, low-dielectric electronic epoxy, high-temperature resistant coatings
Surface modification of quartz powder fundamentally eliminates the natural polarity mismatch between inorganic quartz and organic epoxy resin. It achieves uniform dispersion, strong interfacial bonding, high filling capacity, stable insulation and thermal performance, and better processing performance — all essential to produce high-quality epoxy composites for electronics, adhesives and advanced coatings.
