Elastomeric silicone

Fluorosilicones can be compounded by the addition of mineral fillers and pigments. Fillers for such compounds are most commonly silicas (silicon dioxide), because they are compatible with the elastomeric silicon-oxygen backbone and thermally very stable. They range in surface areas from 0.54 to 400 m2/g and average particle size from 100 to 6 nm. Because of these properties, they offer a great deal of flexibility in reinforcement. Thus, cured compounds can have Durometer A hardness from 40 to 80. Other fillers commonly used in fluorosilicones are calcium carbonate, titanium dioxide, and zinc oxide. 

Additionally, since DOW CORNING 108 emulsion reacts to form an elastomeric silicone polymer, it ... 

One-package elastomeric silicone finish. Provides a durable, full-bodied, lush hand to natural and synthetic fibers. 

SYNTHASIL SE 100 is a nonionic, elastomeric silicone emulsion for treatment of a broad spectrum of natural, synthetic and blended woven or knit goods. The nonionic nature of the product allows for its use with a wide range of nonionic, cationic, anionic and amphoteric surfactants, softeners and lubricants. 

The properties of thermosetting and thermoplastic resin systems are continually improved to meet increasing performance requirements of end users. One way to enhance material properties is to incorporate nano-modifiers, based on elastomeric silicone particles, which are optionally grafted with other (acrylic) polymers to control dispersibility, viscosity, and other parameters. As an example, epoxy resin formulations have been modified with silicone nanospheres to improve low-stress behavior. Table 1 shows the outstanding fracture toughness improvement of silicone coreshell nanospheres, even at very low particle loading levels. 

Elastomeric silicone IPN with TPU and S-EB-S thermoplastic elastomer matrices have found some medical applications [Carew and Deisher, 1989]. The silicone contributes to the excellent release characteristics and to the bio-compatibility. Typical applications include medical tubing, catheters, implants, diaphragms, seals, gaskets, etc. 

Elastomeric silicone sealants first appeared in the early 1950 s. The first of these, patented by J. F. Hyde of Dow Corning Corporation, was a two-part system consisting of an acid-ended polysiloxane and polysilicate.— With this system, materials which cured at room temperature were possible and the term "RTV" (Room Temperature Vulcanizing) was coined. These two-part systems required premixing in appropriate ratios before application and curing. 

Associated with their low moduli and elastomeric properties is their ability to dissipate stresses and to act as stress buffers between harder, less flexible materials such as epoxies. Because of their stress-dissipating properties, soft silicones are often used to bond or encapsulate fragile components such as glass diodes, laser diodes, and electro-optical devices. However, the CTEs of elastomeric silicones are generally... 

Chem. Descrip. Self-crosslinking elastomeric silicone aq. emulsion Uses Adhesion promoter, flexibilizer, water resist, aid, detergent resist, aid in printing inks water repellent, water resist, aid in industrial coatings, parquet varnishes, facade paints, wood coatings, plastic coatings, leather coatings, aq. systems, esp. acrylic disps. 

FQ Elastomeric silicone with fluorine-containing substituents... 

Elastomeric silicones with methyl substituents Methylstyrene-styrene-acrylonitrile-grafted polybutadiene Thermoplastic copolymer from a-methyl styrene and acrylonitrile... 

Vulcanized (cross-linked) polyethylene, also XLPE Elastomeric silicone with vinyl substituents Polydimethylsiloxane with vinyl groups Wide-angle X-ray scattering Woven rovings... 

Fig. 3.2. Ferrite memory cores locked in place on silicone rubber coated glass-cloth with an elastomeric silicone adhesive. The coated glass-cloth forms the top layer of a rigid epoxy-glass printed circuit board, acting as a further buffer against relative expansion and mechanical shocks (Ampex Corp.).

Patel et al. [21] also demonstrated that organotin species such as dialkyltincarboxylates have a significant influence on both the low temperature thermal stability and load bearing characteristics of elastomeric silicone foams. The presence of these catalysts is impKcated in both proposed low temperature degradation mechanisms for condensation-cured RTV silicones. It was also reported that reaction of these tin species with water leads to siloxane chain scission at temperatures >120°C. This conclusion has been further supported by the Sn Mossbauer and NMR studies carried out recently by Labouriau et al. [22]. 

High Frequency Properties and Applications of Elastomeric Silicones 213... 

FQ Elastomeric silicone with fluorine containing substituents (ASTM) see also FSI ( Hochdruck ), i.e., for poly(ethylene)s with mostly low densities see also PEH... 

MQ Elastomeric silicones with methyl substi- OTBG... 

Elastomeric silicone with phenyl substituents (ASTM)... 

TTT Triethyltrimethylenetriamine (WTR) VQ Elastomeric silicone with vinyl substitu-... 

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