Heat-stabilizing additives

It should be noted that many types of stabilizers are employed, and each polymer system is unique and requires its own particular heat-stabilizer additives. 

Both of these approaches are being explored in an effort to take advantage of the striking improvements in light stability achieved without incurring the real, or at least implied, problems of poor heat stability. Additional stabilizers will continue to be screened and optimum formulations will be selected. 

The Control of Thermal Degradation Pathways in Poly(vinyl chloride) by Heat-Stabilizing Additives... 

The silicone polymer backbone is composed of Si-O-Si bonds. This bond is very strong and stable with a bond energy of 87 Kcal/ mole. The polymer can tolerate 250°C to 300°C without decomposing.— The fully compounded silicone sealant, when cured to a rubber, can withstand 200°C for sustained periods of time with no special additives and even higher temperatures with polymer modifications and/or heat stability additives.— The Sl-O-Si molecular structure is also transparent to U.V., so silicone sealants are virtually unaffected by weather. Samples of silicone sealants used in exterior construction applications have been tested after 20 years of actual performance. These samples exhibited essentially no change in physical properties or adhesion during that time period. 

Chem. Descrip. Polyethylene homopolymer CAS 9002-88-4 EINECS/ELINCS 200-815-3 Uses Gellant for oils in personal care prods. film-former oil or fragrance encapsulator nonirritating abrasive emollient heat stabilizer additive for plastics, rubber, adhesives, coatings, inks, paper, polishes, textiles food pkg. adhesives, coatings, paper/paperboard, cellophane, rubber articles, textiles, lubricants defoamer Features Increases permanency, moisture retention, water resist. Regulatory FDA 21 CFR 175.105,175.125,175.300,175.320,176.170,... 

Polyamide thermoplastic elastomers are characterized by their high service temperature under load, good heat aging, and solvent resistance. They retain serviceable properties >120 h 302°F (150°C) without adding heat stabilizers. Addition of a heat stabilizer increases... 

Poly(dimethyl/methylphenyl siloxane)s and poly(dimethyl/diphenyl siloxane)s have been prepared with a range of phenyl contents and their thermal degradations studied. The products of degradation are shown to be benzene and a complex mixture of cyclic oligomers, the latter being analysed by GLC, mass spectrometry, and n.m.r. spectrometry. The mechanism of degradation is discussed in relation to the degradation reactions previously described for (PDMS) and poly(methylphenyl siloxane)s. A study of soluble and insoluble heat stability additives for (PDMS) has been reported and a mechanism of stabilization proposed. ... 

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