Dexerials SC970 low molecular weight silicone flame retardant silicone adhesive (grey)

Product Overview

Dexerials SC970 is a one-component room temperature moisture-curing (RTV-1) flame-retardant silicone adhesive specially developed for high-reliability electronic and electrical assembly.. This product does not use tin-based reaction catalysts, reduces environmental load, is non-corrosive to metal substrates, and has extremely low curing odor.。

SC970 strictly controls and significantly reduces the volatilization of low molecular cyclic siloxane (D3~D10), fundamentally eliminating the risk of insulation failure in electrical contacts such as relays and micro switches due to volatilization and oxidation of siloxane.. The product hasUL94 V-0 flame retardant certification (3.0mm)with excellent high temperature insulation properties, has good thixotropy and does not sag. It is a benchmark material for fixing precision circuit board components, insulating sealing and protecting high-voltage components.。

Core advantages and features

• Ultra-low low molecular weight siloxane (anti-contact failure):After GC-MS testing, the volatilization amount under heating at 100°C is only 253 ppm, and only 309 ppm at 150°C, which is far lower than the level of thousands of ppm of traditional silicone, ensuring long-term conduction of highly sensitive electronic contacts.。

• Authoritative UL94 flame retardant certification:Passed the US UL flame retardant certification, reaching the highest thickness at 3.0mmUL94 V-0Grade, achieved at 1.0mm thicknessUL94 V-1Level (certification code: File No. E63260)。

• Tin-free catalyst, non-corrosive to metals:Environmentally friendly dealcoholization/neutral curing mechanism, no corrosion to copper, iron, aluminum, stainless steel and other metal substrates。

• Fast surface drying and excellent workmanship:Tack-free time at 23℃Within 10 minutes; The paste is non-liquidity paste, the vertical dispensing is not easy to sag, and the tube extrusion is smooth and easy to operate.。

• Excellent thermal conductivity and insulation balance:The thermal conductivity reaches0.7 W/(m·K), withstand voltage strength ≥ 13 kV/mm, insulation resistance maintained at$10^{12} Omega$above。

• Environmentally friendly and compliant:Comply with EU RoHS environmental standards and completely free of halogen compounds (halogen-free)。

Basic physical properties and specifications

Electrical insulation and reliability data

1. Electrical insulation properties (23℃ × 60% RH × 7 days curing)

• Volume resistivity: $2.0 imes 10^{10} Omegacdot ext{m}$

• Surface insulation resistance (comb electrode 1.27mm spacing): $ge 10^{12} Omega$(After 1000 hours of moist heat aging at 60℃ × 90% RH, it is still stable at$6.2 imes 10^{12} Omega$; Aging at 100℃ for 1000 hours can reach$7.0 imes 10^{13} Omega$）

• Withstand voltage breakdown strength (JIS C2110): $ge 13 ext{kV/mm}$

• Dielectric constant (1 MHz, JIS K6249): $le 4$

• Dielectric loss tangent (1 MHz, JIS K6249): $le 0.01$

2. Comparison of low molecular weight siloxane volatilization (GC-MS measurement, D3~D10 conversion)

• 100℃ heating:SC970 only253 ppm(Compared to conventional models SC901: 1,104 ppm / SC950: 1,901 ppm)

• 150℃ heating:SC970 only309 ppm(Compared to conventional models SC901: 3,179 ppm / SC950: 4,196 ppm)

3. Shear bonding strength of each material (adhesive layer 1mm, area 25×10mm)

• Engineering plastics adhere to each other (aging at 60°C × 168h):

• ABS / ABS: Initial 201 N/cm$ ightarrow$After aging267 N/cm

• PMMA / PMMA: Initial 186 N/cm$ ightarrow$After aging 187 N/cm

• Rigid PVC/PVC: Initial 194 N/cm$ ightarrow$After aging 151 N/cm

• Phenolic resin / Phenolic resin: Initial 199 N/cm$ ightarrow$After aging 193 N/cm

• Bonding of circuit board and metal (after 100℃ × 168h high temperature aging):

• Fiberglass epoxy board (FR-4 / FR-4): Initial 226 N/cm$ ightarrow$After aging234 N/cm

• Copper plate (C1100P / C1100P): Initial 172 N/cm$ ightarrow$After aging 169 N/cm

• Galvanized steel (SECC / SECC): Initial 152 N/cm$ ightarrow$After aging174 N/cm

• Aluminum plate (A5052P / A5052P): Initial 151 N/cm$ ightarrow$After aging182 N/cm

Typical application areas

1. PCB circuit board component reinforcement:Shockproof, anti-fall and anti-impact glue dispensing fixation of electrolytic capacitors, inductors, large filter capacitors and other plug-in components。

2. Insulation and sealing of high-voltage components:High-voltage insulated packaging for flyback transformers (FBTs), high-voltage power packs, rectifiers and hybrid integrated circuits (Hybrid ICs)。

3. Sensors and Sensitive Electronic Modules:Potting of various temperature and pressure sensor probes, as well as anti-vibration and moisture-proof bonding near vehicle controllers and micro switches。

4. Special scenarios for preventing electrical contact failure:Assemblies of optoelectronic/electrical components that have extremely strict requirements on siloxane volatilization, such as closed relay boxes and communication module boxes.。

Construction technology and curing characteristics

1. Curing mechanism:This product relies on moisture in the air to gradually promote the reaction from the surface to the inside (under the conditions of 23℃ × 60% RH, the curing depth is about 4mm in 3 days, and reaches more than 7mm in 7 days). The actual complete hardening time is affected by the construction thickness, workshop temperature and humidity and sealing degree。

2. Substrate cleaning:Before coating, please ensure that the surface of the parts to be bonded is free of grease, flux residue, moisture and dust.。

3. Storage suggestions:Store in a cool, dry and ventilated place at room temperature away from light, away from fire sources. After opening, be sure to seal the nozzle to prevent moisture from entering and causing skinning on the nozzle.。