Novel Thermally Triggered Catalyst/Promoter Additives for Unsaturated Polyester, Vinyl Ester and Epoxy Resin Cure

摘要

Novel side-chain crystalline (SCC) polymer additives have been developed incorporating catalyst or promoter functionality that can be thermally triggered at preset activation temperatures. These SCC polymer additives provide shelf-life and pot-life extension for a variety of thermoset systems including: (a) cobalt/other metal accelerators for unsaturated polyesters or vinyl esters (b) imidazole and tertiary amine catalysts for epoxies, and (c) tin and tertiary amine catalysts for polyurethanes. These SCC polymer additives provide a controlled catalyst/promoter thermal triggering mechanism tunable within 1 deg C of any temperature between 0-100 deg C. Conventional and new catalysts/promoters can be physically or chemically bound to these SCC polymers providing temperature controlled catalyst/promoter delivery. These polymer additives are available as small particle size (< 10 micron) easy to disperse powders. Unsaturated polyester formulations with thermally triggered cobalt polymer additive and MEK peroxide exhibit dramatically extended room temperature pot-life while yielding comparable 80-120 deg C cure times, Tg and modulus values at both 30 and 120 deg C versus cobalt naphthenate control. Latent thermally triggered polymer additive catalysts with 15-30percent imidazole moieties, melting between 50-100 deg C allow economic epoxy system formulation with 1-6-month 40 deg C shgelf stability, 80-120 deg C reactivity and comparable mechanical properites versus imidazole control. These latent catalyst/promoter polymer additives provide shelf-life and pot-life extension opportunities in shop and field applications for SMC, BMC, reinforced in- jection molding, filament winding/pultrusion, and other polyester, vinyl ester, and epoxy resin composite systems.