摘要:
Embodiments include polymer polyol dispersions which include a polyol liquid phase and solid particle phase. Embodiments include methods of making the polymer polyol dispersions. The polymer polyol dispersions are essentially free of tin, have a solid content of between about 20 and 50 wt% based on the total weight of the polymer polyol dispersion, and have a viscosity at 20C of less than 9000 mPas. The solid particle phase has more than 90% by weight of particles in the solid particle phase having a particle diameter of less than 5 µm.
摘要:
Embodiments of the invention include a method of producing polymer polyol dispersions is. The method includes providing at least one reaction system, and the reaction system includes: a) at least one polyol, b) at least one seed population, c) at least one catalyst, d) at least one co-reactant having an equivalent weight of up to 400 and at least one active hydrogen attached to a nitrogen or oxygen atom, and e) at least one polyisocyanate. The at least one seed population includes less than about 5% by weight of the total weight of the at least one reaction system and includes seed particles having diameters of less than 5 µm. The at least one reaction mixture reacts to form at least one of a polyurea and polyurethane-urea particle population in the at least one polyol without the addition of any catalysts comprising tin. The polymer polyol dispersion has a solids content of at least 15% of the weight of the polymer polyol dispersion.
摘要:
Copolymers of propylene oxide and ethylene oxide have an inner block that contains from 65-90 weight percent oxyethylene units and from 10 to 35 weight percent oxypropylene units. This block has a molecular weight of from 150 to 350. The copolymer has an outer block which contains at least 95 weight % oxypropylene units and from 0 to 5% oxyethylene units. The equivalent weight of the copolymer is from 800 to 2000. The copolymers are useful in making polyurethane foams that have unexpectedly high tensile and/or tear strengths.