Bk-7801 low molecular weight hydroxyl silicone oil
Boctok, as a leading enterprise in silicone field in China, launched low molecular hydroxyl silicone oil-40cs, which becomes a "star additive" in rubber, automobile, chemical, textile and other industries due to its excellent performance and wide range of application scenarios.
1. Product introduction
1.1 Product overview
Boctok low molecular weight hydroxyl silicone oil-40cs is a silicone compound with low molecular weight and moderate viscosity. It contains an active hydroxyl group (o) at the end of the molecular chain, which combines the excellent performance and reaction of silicone oil, and is widely used in textile, cosmetic, industrial lubrication, rubber and plastic processing.
This product has the characteristics of high permeability, dispersion, heat resistance and environmental protection, and is widely used as a structure control agent in silicone rubber processing, can effectively control the structure interaction between the compound and silicone, improve the processing efficiency of silicone rubber, extend the shelf life of rubber, shorten the reforming time, gel formation volume, rubber moment viscosity, vulcanized rubber hardness, permanent deformation and so on.
1.2 product properties
Appearance: colorless transparent fatty liquid
Viscosity (25°):40° 5° with
Hydroxyl content:4 %
Volatile substances (150 /3h):18 %
Refractive index:1.4040~1.410040 cs
Low VOC and total body cycling!
2. Application in rubber mixing part
Boctox Low Molecular Weight Hydroxyl Silicone Oil - 40HN plays an important role in the preparation and processing of rubber due to its unique chemical structure and physical properties. The following is a detailed description of its application based on the mechanism of action, specific application scenarios, advantages and precautions.
2.1 mechanism
Lubricant and dispersion:Low molecular hydroxyl silicone oil with low viscosity (40 ± 5 cSt) gives it excellent viscosity, can penetrate into the rubber matrix evenly, reduce the internal friction between the rubber molecular chain, so as to improve the processing fluidity of rubber. At the same time, its hydroxyl group (o) can form a hydrogen bond with the surface of fillers (such as silicon, carbon), promoting the dispersion of fillers in the rubber, reducing agglomeration and improving the mixing efficiency.
Internal mold release function:In the mixing process, hydroxyl silicone oil can be used as an internal mold release agent, moving to the surface of the rubber, forming a very thin lubricating film, reducing the adhesion between the rubber and the metal rollers or molds, avoiding sticking to the rollers and improving the continuity of production.
Promoting cross-linking and modification:The active hydroxyl group of silicone oil can be bonded with certain functional groups in rubber (e.g. silicone rubber in SI-o or hydrogenated silicone oil in SI-n) by condensation reaction to help control the cross-linking density, optimize the mechanical properties of vulcanized rubber. In addition, in the silicone rubber system, hydroxyl silicone oil can also be used as a structure control agent to suppress the structure effect (i.e. "agglomeration compaction") caused by hydroxyl
2.2 specific application scenarios
2.2.1 Improving the efficiency of data processing
Reducing the viscosity of the mooney:In natural rubber (NR), styrene butadiene rubber (SBR) or EPDM and other high viscosity rubbers, adding 1%~3% hydroxyl silicone oil can significantly reduce the viscosity of the Mooney rubber compound, reduce the energy consumption of the equipment, shorten the mixing time.
Reduce the risk of burnout:by reducing the generation of surface heat, slow down the burning process during mixing, especially when processing highly filled compositions.
2.2.2 Filler dispersion enhancement
Dispersion of silica:In silicone rubber (e.g. VMQ) or solubilized styrene butadiene rubber (SSBR) for green tyres, hydroxyl silicone oil combines with the silicon hydroxyl group on the surface of silica, weakening the hydrogen bonding between fillers, preventing the formation of filler network, and enhancing the reinforcing effect.
Carbon black dispersion:In carbon black-filled natural rubber (NR) or styrene-butadiene rubber (SBR) system, hydroxyl silicone oil is used as a dispersing additive to reduce carbon black aggregation and improve the homogeneity and mechanical properties of the rubber.
2.2.3 internal release and surface modification:
In EPDM seals or NBR oil-resistant rubber, adding 0.5%~1.5% hydroxyl silicone oil can reduce the rubber in the opening machine or refinery in the sticky roller phenomenon, while ensuring the vulcanized rubber coating smoothness, reduce the subsequent use of releasing agents, improve production efficiency and reduce production costs.
3. Application in molding rubber
3.1 mold removal and lubrication
Mechanism: The molecular chain of hydroxyl silicone oil is short, strong migration, can form a dynamic insulation film on the surface of the mold, reduce the adhesion between rubber and mold (the friction coefficient can be reduced by 30%-50%).
Data support: Adding 1-3% hydroxyl silicone oil 40xc can reduce the ejection force by 40%-60%, which is especially suitable for complex mold structures (such as precision electronic component encapsulation molds).
Limitation of side effects: Excessive addition (>5%) may result in surface oil deposits of the product, need to improve compatibility by dynamic vulcanization or combination with gas phase silica.
3.2 increasing the fluidity of the glue
Low viscosity significantly reduces the meniscal viscosity of rubber (ml (1+4) 100 ℃ can be reduced by 10-20 points), shortens the molding cycle (such as the molding time of EPDM rubber from 180 to 150). In the high-temperature vulcanization stage (150-180 degrees), hydroxyl groups can be combined with the peroxide cross-linking system to form SI-o-s bonds, which improves the cross-linking efficiency (the cross-linking density increased by 5%-8%).
3.3 Optimization of filler dispersion
Hydroxyl and silium, and other silicon hydroxyl surface of the filler (sio-o) to form hydrogen bonds, reducing the possibility of filler agglomeration. Experiments show that adding 2% hydroxyl silicone oil can improve the dispersion (observation of topics) of carbon black /N330 in silicone rubber to be uniformly distributed in the nanoscale.
4. Other uses
Antifoam, Personal Care, Paper Processing, Textiles, Rubber Manufacturing, Rubber and Plastics Processing, Automotive, Leather, Coatings and Paints.