Silicone aliphatic polyesters

The molar mass of the polyesters depended on the reaction temperature, enzyme activity, enzyme concentration, and to a lower extent on the applied vacuum. For example, when the polyesters were synthesized using 1,4-butanediol, 1,6-hexanediol and 1,8-octanediol in the bulk at 70°C under reduced pressure for 24 hours, the weight average molecular weights obtained were 15,100 g moF, 16,000 g mol, and 16,700 g mof , respectively. Thermal analysis of these copolymers revealed no melting phenomenon, perhaps due to the presence of the bulky and flexible siloxane segments in 

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Synthesis of linear silicone aliphatic polyesters by the condensation polymerization of l,3-bis(3-carboxypropyl)tetra-methyldisiloxane with alkanediols (1,4-butanediol, 1,6-hex-anediol and 1,8-octanediol) using an immobilized lipase B from Candida antarctica (Novozym-435) as a catalyst, as shown in Scheme 2.2, has been reported [21]. These reactions were performed in the bulk (without the use of solvent) in the temperature range 50-90°C under reduced pressure (50-300 mmHg, vacuum gauge). 

Chem. Descrip. Aliphatic silicone-modified polyester polyurethane waterborne disp. with n-methyl pyrrolidone cosolv. 

Regenerated cellulose, cellulose acetate, polyacrylonitrile, polysulfone Nylon, polyester, silk Aliphatic polyesters, regenerated collagen PMMA, UHMWPE Polyester, PTFE Silicones, polyurethanes Silicones... 

Aliphatic organofunctional silanes recommended as coupling agents for glass-reinforced polyesters, epoxies, or phenolics have heat stabilities of typical aliphatic organic chemicals and are not at all comparable to the methyl or phenyl silicones found in silicone polymers and resins. 

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