Flame and smoke spread retardant molding compounds and components molded from these compounds
HVAC and building and construction components are molded from novel compositions that meet the flame spread and smoke index, as well as the molding, safety, strength, and aesthetic requirements for this use. These compounds are based on a polyester resin and more specifically can be an polypropylene glycol dicyclopentadiene copolymerized with maleic anhydride, a low profile additive and hydroxy ethyl methacrylate monomer with additional additives including an appropriate catalyst package, a mold release agent, a thickening agent, a loading of aluminum hydroxide which is from about 40 to 65% by weight, and having a loading of glass fibers of from about 10 to about 25%.
1. A component for an air handler or hot air furnace which is a molded product of a molding composition comprising:
a) a thermoset resin system comprising: an unsaturated polyester and reactive monomers;
wherein the unsaturated polyester is a product of a condensation polymerization reaction between monomers consisting of propylene glycol, dicyclopentadiene, and maleic anhydride;
wherein the reactive monomers comprise styrene and hydroxyethyl methacrylate;
wherein the unsaturated polyester is dissolved in the reactive monomers;
wherein the ratio of the reactive monomers to the unsaturated polyester resin is from 5:95 to 50:50;
wherein the thermoset resin system is blended with from 20% to 45% by weight of the thermoset resin system of a low profile additive selected from the group consisting of polymethylmethacrylate, polyethylmethacrylate, polystyrene, polystyrene copolymer, polyvinyl acetate, polyethylene, saturated polyester, vinyl chloride-vinyl acetate copolymer, polyurethane, styrene butadiene copolymer, polycaprolactone, cellulose acetate butyrate, and combinations thereof;
b) from 10% to 30% by weight of glass fiber, based on the weight of the molding composition;
c) from 0.05% to 5% by weight of an initiator, based on the weight of the molding composition; and
d) from 250 to 450 pph of a flame retardant composition consisting of aluminum hydroxide, based on the weight of the thermoset resin system;
whereby the molding composition when molded meets the standard of UL 723.
2. The component of claim 1 , further comprising from 0.5 to 10 phr of mold release agent, based on the thermoset resin system.
3. The composition of claim 1 , wherein the composition does not comprise more than 10% by weight styrene, based on the weight of the molding composition.
4. The component of claim 1 , wherein the glass fiber is from 15% to 25% by weight, based on the weight of the molding composition.
5. The component of claim 1 , further comprising from 0.1% to 2% by weight of a thickening agent, based on the weight of the molding composition.
6. The component of claim 5 , wherein the thickening agent is magnesium oxide or magnesium hydroxide.
7. The component of claim 1 , wherein the component is a drain pan, a base pan, or a blower housing.
8. A molding composition comprising:
a) a thermoset resin system comprising: comprising: an unsaturated polyester and reactive monomers;
wherein the unsaturated polyester is a product of a condensation polymerization reaction between monomers consisting of propylene glycol, dicyclopentadiene, and maleic anhydride;
wherein the reactive monomers comprise styrene and hydroxyethyl methacrylate;
wherein the unsaturated polyester is dissolved in the reactive monomers;
wherein the ratio of reactive monomers to the unsaturated polyester is from 5:95 to 50:50;
wherein the thermoset resin system is blended with from 20% to 45% by weight of the thermoset resin system of a low profile additive selected from the group consisting of polymethylmethacrylate, polyethylmethacrylate, polystyrene, polystyrene copolymers, polyvinyl acetate, polyethylene, saturated polyesters, vinyl chloride-vinyl acetate copolymers, polyurethanes, styrene butadiene copolymers, polycaprolactone, cellulose acetate butyrate, and combinations thereof;
b) from 10% to 30% of glass fiber, based on the weight of the molding composition;
c) from 0.05% to 5% of an initiator, based on the weight of the molding composition; and
d) from 250 to 450 pph of a flame retardant composition consisting of aluminum hydroxide, based on the weight of the thermoset resin system;
whereby the molding composition when molded meets the standard of UL 723.
9. The composition of claim 8 , wherein the composition does not comprise more than 10% by weight styrene, based on the weight of the molding composition.
10. The composition of claim 8 , wherein the glass fiber is from 15% to 25% by weight, based on the weight of the molding composition.
11. The composition of claim 8 , wherein the amount of glass fiber comprises from 18% to 23% by weight, based on the weight of the molding composition.
12. The composition of claim 8 , further comprising from 0.5 to 10 phr of a mold release agent, based on the thermoset resin system.
13. The composition of claim 8 , further comprising from 0.1% to 2% of a thickening agent, based on the weight of the molding composition.
14. The composition of claim 13 , wherein the thickening agent is magnesium oxide or magnesium hydroxide.