Process for making high resilience foams
AssigneeHuntsman International LLC
InventorsAlain Parfondry, Jianming Yu
Life of this patent
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Abstract
A prepolymer process for preparing a high resilience flexible polyurethane foam by reacting a polyisocyanate composition comprising at least 80% by weight of 4,4′-MDI and having an NCO value below 20% with a polyol composition comprising b1) an EO-rich polyol; b2) a polyol with an EO content between 20-50% and a primary hydroxy content of at least 50%; and b3) a polyol with an EO content between 10-20% and a primary hydroxy content of at least 50%; according to the following proportions: b1: 40-90 wt %, b2: 5-60 wt %, b3: 0-20 wt %. The invention also relates to reaction systems comprising the above components.
Claims20
A process for preparing a high resilience flexible polyurethane foam at an NCO index of 70-120, which process is a prepolymer process, by reacting:
- a) a polyisocyanate composition comprising at least 80% by weight of 4,4′-MDI;
- b1) a polyoxyethylene-polyoxypropylene polyol, having an average nominal hydroxy functionality of 2-6, where the EO is present as tipped EO and/or random EO, the total EO content being at least 50% by weight;
- b2) a polyoxyethylene-polyoxypropylene polyol, having an average nominal hydroxy functionality of 2-6, where the EO is present as tipped EO and/or random EO, the total EO content being between 20-50% by weight, having a primary hydroxy content of at least 50%;
- and optionally
- b3) a polyoxyethylene-polyoxypropylene polyol, having an average nominal hydroxyl functionality of 2-6, having a primary hydroxy content of at least 50%, and having an EO content of from 10 to 20% by weight;
- these polyols b1, b2 and b3 being reacted according to the following proportions, based on the combined weights of b1, b2 and b3, b1:
- 40-90 wt %, b2:
- 5-60 wt %, b3:
- 0-20 wt %;
- c) water;
- and
- d) additives and auxiliaries known per se;
- and where a polyisocyanate prepolymer is used which has an NCO value below 20% by weight.
A reaction system comprising A) a polyisocyanate prepolymer having an NCO value of from 7 to 20% by weight, obtained by reacting a polyisocyanate with part of a polyol composition, and B) an isocyanate-reactive component comprising the remainder of the polyol composition and water, wherein the polyol composition comprises:
- b1) a polyoxyethylene-polyoxypropylene polyol, having an average nominal hydroxy functionality of 2-6, where the EO is present as tipped EO and/or random EO, the total EO content being at least 50% by weight;
- b2) a polyoxyethylene-polyoxypropylene polyol, having an average nominal hydroxy functionality of 2-6, where the EO is present as tipped EO and/or random EO, the total EO content being between 20-50% by weight, having a primary hydroxy content of at least 50%;
- and optionally
- b3) a polyoxyethylene-polyoxypropylene polyol, having an average nominal hydroxyl functionality of 2-6, having a primary hydroxy content of at least 50%, and having an EO content of from 10 to 20% by weight;
- these polyols b1, b2 and b3 being used according to the following proportions, based on the combined weights of b1, b2 and b3, b1:
- 40-90 wt %, b2:
- 5-60 wt %, b3 0-20 wt %.
Dependencies are inferred from the claim text.