Polystyrene-block-poly(2-cinnamoylethyl methacrylate) (PS-b-PCEMA) formed micelles in THF/cyclohexane or chloroform/cyclohexane mixtures with the PCEMA block as the core. Depending on the relative length of the PS and PCEMA block, star and crewcut micelles were prepared. Upon UV irradiation, the PCEMA block selectively cross-linked to form star polymers and nanospheres from the corresponding star and crewcut micelles. The cross-linked micelles were characterized by solution and solid-state NMR, FTIR, GPC, TEM, and dynamic and static light scattering.

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Both HCFC-and pentane-blown rigid polyurethane foams have been prepared from polyols derived from soybean oil. The effect of formulation variables on foam properties was studied by altering the types and amounts of catalyst, surfactant, water, crosslinker, blowing agent, and isocyanate, respectively. While compressive strength of the soy foams is optimal at 2 pph of surfactant B-8404, it increases with increasing the amount of water, glycerin, and isocyanate. It also increases linearly with foam density. These foams were found to have comparable mechanical and thermoinsulating properties to foams of petrochemical origin. A comparison in the thermal and thermooxidative behaviors of soy-and PPO-based foams revealed that the former is more stable toward both thermal degradation and thermal oxidation. The lack of ether linkages in the soy-based rather than in PPO-based polyols is thought to be the origin of improved thermal and thermo-oxidative stabilities of soy-based foams.

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