Polymer wood composite material and method of making same

1 . A polymer wood composite material comprising: a polymeric component; wood flour; a coupling agent; a thermal stabilizer component; a plasticizer; a foaming agent; and a pigment;

wherein the composite material exhibits less than 1% thickness swelling and less than 5% by weight water absorption when submerged in water for at least 24 hours, wherein thickness swelling is measured as a percentage of original thickness; and

wherein the composite material has a hardness which is greater than or equal to natural pine wood as measured on the Rockwell C Hardness scale.

2 . The composite material of claim 1 , wherein:

the polymeric component includes a polyvinyl chloride resin selected from the group consisting of a polyvinyl chloride homopolymer having an inherent viscosity in the range of about 0.65 to 0.94, a polyvinyl chloride copolymer having an inherent viscosity in the range of about 0.65 to 0.94, a polyvinyl chloride terpolymer having an inherent viscosity in the range of about 0.65 to 0.94, and a mixture of polyvinyl chloride polymers having an inherent viscosity in the range of about 0.65 to 0.94;

the wood flour includes a member selected from the group consisting of hard wood flour having a size in the range of 40 mesh to 140 mesh, soft wood flour having a size in the range of 40 mesh to 140 mesh, and a combination of hard and soft wood flour having a size in the range of 40 mesh to 140 mesh;

the coupling agent includes an aminosilane, a mercaptosilane or an alkanolamine;

the thermal stabilizer component includes a liquid mercaptide;

the plasticizer includes a phthalate, a terephthalate, a benzoate, a trimellitate, a pentaerythritol, an adipate, an azelate, a glutarate or a sebacate;

the foaming agent includes an exothermic foaming agent, an endothermic foaming agent, or a mixture of an exothermic foaming agent and an endothermic foaming agent; and

the pigment includes titanium dioxide in a natural color.

3 . The composite material of claim 2 , wherein:

the polyvinyl chloride resin is present in an amount in the range of about 51 to 70 weight percent of the composite material;

the wood flour is present in an amount in the range of about 26 to 35 phr;

the coupling agent includes an aminosilane which is present in an amount in the range of about 0.5 to 3.0 phr;

the liquid mercaptide is present in an amount in the range of about 0.5 to 3.0 phr;

the plasticizer includes diisononyl phthalate which is present in an amount in the range of about 1.0 to 4.0 phr;

the foaming agent includes an azodicarbonamide which is present in an amount in the range of about 0.8 to 2.5 phr; and

the titanium dioxide in a natural color is present in an amount in the range of about 0.5 to 3.0 phr.

4 . The composite material of claim 3 , wherein:

the polyvinyl chloride resin is present in an amount of about 58% by weight of the composite material;

the wood flour includes Maple hard wood flour having a size of 80 mesh, which is present in an amount of about 32 phr;

the aminosilane is present in an amount of about 1.0 phr;

the liquid mercaptide is present in an amount of about 1.8 phr;

the diisononyl phthalate is present in an amount of about 3.0 phr;

the azodicarbonamide is present in an amount of about 2.5 phr; and

the titanium dioxide in a natural color is present in an amount of about 2.0 phr.

5 . A building component comprising the composite material of claim 1 .

6 . The building component of claim 5 , wherein the building component is selected from the group consisting of a doorjamb, a doorsill, a brick mold, a door stile, and a door rail.

7 . The building component of claim 6 , wherein the building component is a doorjamb.

8 . A building component comprising the composite material of claim 2 .

9 . The building component of claim 8 , wherein the building component is selected from the group consisting of a doorjamb, a doorsill, a brick mold, a door stile and a door rail.

10 . The building component of claim 9 , wherein the building component is a doorjamb.

11 . A building component comprising the composite material of claim 3 .

12 . The building component of claim 11 , wherein the building component is selected from the group consisting of a doorjamb, a doorsill, a brick mold, a door stile and a door rail.

13 . The building component of claim 12 , wherein the building component is a doorjamb.

14 . A building component comprising the composite material of claim 4 .

15 . The building component of claim 14 , wherein the building component is selected from the group consisting of a doorjamb, a doorsill, a brick mold, a door stile and a door rail.

16 . The building component of claim 15 , wherein the building component is a doorjamb.

17 . A method of producing an extrudable mixture for an extrusion process in producing a polymer wood composite material, the method comprising:

adding a polymeric component and a coupling agent to a high intensity mixer bowl;

mixing the polymeric component and the coupling agent for at least about ten seconds to form a first mixture;

adding a thermal stabilizer component to the first mixture to form a second mixture;

mixing the second mixture for at least about one minute;

adding wood flour to the mixed second mixture to form a third mixture;

heating the third mixture to a temperature in the range of about 210 to 220° F.;

adding a lubricant-stabilizer to the heated third mixture to form a fourth mixture;

heating the fourth mixture to a temperature in the range of about 210 to 220° F.;

adding a plasticizer to the heated fourth mixture to form a fifth mixture;

heating the fifth mixture to a temperature in the range of about 215 to 225° F.;

adding a filler to the heated fifth mixture to form a sixth mixture;

heating the sixth mixture to a temperature in the range of about 255 to 265° F.;

removing the heated sixth mixture from the high intensity mixer bowl, and decreasing its temperature to about 104° F. or less, thereby forming the extrudable mixture.

18 . The method of claim 17 , wherein the lubricant-stabilizer comprises at least one processing aid, an impact modifier, at least one wax, a lubricant, a pigment and a foaming agent.

19 . The method of claim 18 , wherein:

the polymeric component includes a polyvinyl chloride resin selected from the group consisting of a polyvinyl chloride homopolymer having an inherent viscosity in the range of about 0.65 to 0.94, a polyvinyl chloride copolymer having an inherent viscosity in the range of about 0.65 to 0.94, and a polyvinyl chloride terpolymer having an inherent viscosity in the range of about 0.65 to 0.94;

the coupling agent includes an aminosilane, a mercaptosilane or an alkanolamine;

the thermal stabilizer component includes a liquid mercaptide;

the wood flour includes a member selected from the group consisting of hard wood flour having a size in the range of 40 mesh to 140 mesh, soft wood flour having a size in the range of 40 mesh to 140 mesh, and a combination of hard and soft wood flour having a size in the range of 40 mesh to 140 mesh;

the at least one wax includes a stearate ester wax and at least one polyethylene wax;

the lubricant includes calcium stearate;

the pigment includes titanium dioxide in a natural color;

the foaming agent includes an exothermic foaming agent, an endothermic foaming agent, or a mixture of an exothermic foaming agent and an endothermic foaming agent;

the plasticizer includes a phthalate, a terephthalate, a benzoate, a trimellitate, a pentaerythritol, an adipate, an azelate, a glutarate or a sebacate; and

the filler includes CaCO 3 .

20 . The method of claim 19 , wherein:

the polyvinyl chloride resin is present in an amount in the range of about 51 to 70 weight percent of the polymer wood composite material;

the coupling agent includes an aminosilane which is present in an amount in the range of about 0.5 to 3.0 phr;

the liquid mercaptide is present in an amount in the range of about 0.5 to 3.0 phr;

the wood flour includes a Maple hard wood flour having a size of 80 mesh which is present in an amount in the range of about 26 to 35 phr;

the stearate ester wax is present in an amount in the range of about 0.5 to 3.0 phr;

the at least one polyethylene wax is present in an amount in the range of about 0.2 to 2.0 phr;

the calcium stearate is present in an amount in the range of about 0.5 to 3.0 phr;

the titanium dioxide in a natural color is present in an amount in the range of about 0.5 to 3.0 phr;

the foaming agent includes an azodicarbonamide which is present in an amount in the range of about 0.8 to 2.5 phr;

the plasticizer includes diisononyl phthalate which is present in an amount in the range of about 1.0 to 4.0 phr; and

the CaCO 3 is present in an amount in the range of about 5 to 15 phr.

21 . The method of claim 20 , wherein:

the polyvinyl chloride resin is present in an amount of about 156.26 pounds;

the aminosilane is present in an amount of about 1.56 pounds;

the liquid mercaptide is present in an amount of about 2.81 pounds;

the Maple hard wood flour having a size of 80 mesh is present in an amount of about 50.0 pounds;

the stearate ester wax is present in an amount of about 2.50 pounds;

the at least one polyethylene wax is present in an amount of about 2.19 pounds;

the calcium stearate is present in an amount of about 3.13 pounds;

the titanium dioxide in a natural color is present in an amount of about 3.13 pounds;

the azodicarbonamide is present in an amount of about 3.91 pounds;

the diisononyl phthalate is present in an amount of about 4.69 pounds; and

the CaCO 3 is present in an amount of about 12.50 pounds.