Tospearl

Perry, R. J. Adams, M. E. TOSPEARL Silicone Resin for Industrial Applications. In Silicones and Silicone-Modified Materials-, Clarson, S. J., Fitzgerald, J. J., Owen, M. J., Smith, S. D., Eds. AGS Symposium Series 729 American Chemical Society ... 

Uses Emollient in cosmetics lubricant, slip agent, water repellent for skin care, pigmented cosmetics surf, lubricant, antiblocking agent for food-contact polyolefin films Regulatory FDA 21 CFR 177.1520 Trade Names Tospearl 2000B... 

Tospearl 2000B aigicide, indoor damp room emulsion... 

Supersllp 6520 Tospearl 2000B gloss control aid, paints/coatings DIaFII 525 DiaFil 530 DiaFil 570 DIaFII 590 Microspersion 440W Micron 665 Propylmatte 31 gloss control aid, plastic coatings Supersllp 6520... 

Tospearl 120A] Tospearl 130A] Tospearl 145A] Tospearl 2000] Tospearl 2000B. See Poiymethyisiisesquioxane Tosyiamide p-Tosyiamide. See p-Toiuenesuifonamide Tosyiamide/epoxy resin Synonyms Toiuenesuifonamide/epoxy resin Definition Toluenesulfonamide of the condensation prod, of 4,4 -isopropylidenediphenol with epichlorohydrin, also known as the diglycidyl ether of bisphenol A... 

Polymethylsilsesquioxane Si-Tec PMS Tospearl 120A Tospearl 130A Tospearl 145A Tospearl 2000 Tospearl 2000B... 

A fine-particle silicone additive has been developed by GE Silicones to improve the surface and surface Interaction characteristics of polymers, rubbers and similar materials. A key application for the additive (Tospearl) is an antiblocking agent for thin plastics film. Added to the resin during compounding, the fine particle spheres (0.5 12 pm) protrude from the surface of the blown film to form a uniformly uneven surface that prevents adhesion between film layers. The particle size is selected depending on film thickness. The spherical shape of the particles, combined with good inherent lubricity of silicone, also improves the slip characteristics of the film. 

Figure 17.1. With an average particle diameter of 4.5 fini. Tospearl is an advanced silicone anti-blocking...

Tospearl silicone anti-blocking agent GE Silicones... 

A unique, amorphous T resin particle has been reported (541). This material, known by the trade name Tospearl (Tospearl is a trademark of the General Electric Co.), is a spherical resin particle made by the controlled, base-catalyzed hydrolysis and condensation of CHsSilOCHsla (eq. 43). 

Highly cross-linked spheres with an average particle size from 0.5 to 12.0 /rm have been produced. Extremely narrow particle size distributions are possible. The particle size and degree of monodispersivity are controlled by kinetic factors during the hydrolysis. Applications for Tospearl powders include wear resistance, antiblocking properties, light-diffusion control, and lubrication (542). 

Tospearl particles are crosslinked siloxanes made by the controlled hydrolysis and condensation of methyltrimethoxysilane. Their spherical nature, narrow particle size distribution and chemical and thermal stability make them ideal for use in wear resistance, antiblocking and light diffusing applications. 

Tospearl is a spherical silicone resin particle made by the controlled hydrolysis and condensation of alkyl trialkoxysilanes (equation 1) and produced by Toshiba Silicones, a joint venture of GE Silicones. The first report of these materials appeared in 1985 when the aqueous amine catalyzed condensation of methyl trimethoxysilane was described (1). Since the initial disclosure, a number of other patents have issued in this area (2-8). The product is a tluee-dimensional network that is intermediate between inorganic and organic particles. This paper describes the physical and chemical properties of this network as well as its utility in a number of applications. 

There are a number of grades of Tospearl produced with sizes ranging form submicron to 12pm. Each of these materials has its own characteristic production process but the... 

Tospearl Diameter (pm) Bulk sp. gr. Specific Surface Area (m /g)... 

As expected for a material that is primarily inorganic, the thermal stability of the silicone resin spheres is extremely high, especially when compared to fine organic particles, as shown in Figure 7. Tospearl 120 was stable to 400+°C in air and at 800°C, there was only 10% weight loss. The weight loss seen at 450 0 is attributed to further condensation within the particle with loss of water and/or methanol. 

Tospearl particles are also readily dispersed in a variety of solvents. Table 2 shows the dispersion viscosity of Tospearl 120 in polar and nonpolar solvents. In polar ketone, alcohol and ether solvents, the viscosities are quite low. When nonpolar or chlorinated solvents are used, the dispersion viscosities rise by an order of magnitude. The polar solvents more readily associate with the residual silanol groups on the Tospearl particles effectively isolating them from self-association. In non-polar solvents, self-association is possible and the viscosity rises accordingly. 

Tospearl 120. . PTFE powder > - Acrylic Resin powder... 

Figure 7. Thermogravimetric Analysis of Tospearl 120 and Organic Resin Fine particles.

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