USOO5981067A United States Patent (19) 11 Patent Number: 5,981,067 Seethamraju et al. (45) Date of Patent: *Nov. 9, 1999 54 ADVANCED COMPATIBLE POLYMER “Use of Wood Fiber as Filler in Common Thermoplastics: WOOD FIBER COMPOSITE Studies on Mechanical Properties”, R. G. Raj et al., Science and Engineering of Composite Materials, 1989, vol. 1, No. 75 Inventors: Kasyap V. Seethamraju, St. Paul; Neil 3, pp. 85–98. J. Beaverson, Hugo; Kurt E. Heikkila, “Effect of Solid-State Modified Polypropylene on the Physi Circle Pines, all of Minn. cal Performance on Sawdust-Filled Polypropylene Compos ites”, M. M. Sain et al., Advances in Polymer Technology, 73 Assignee: Andersen Corporation, Bayport, Minn. 1993, vol. 12, No. 2, pp. 167–183. “The Nature of Adhesion in Composites of Modified Cel * Notice: This patent is Subject to a terminal dis lulose Fibers and Polypropylene”, Johan M. Felix et al., claimer. Journal of Applied Polymer Science, 1991, vol. 42, pp. 609-62O. 21 Appl. No.: 08/949,360 “Composites of Wood and Polypropylenes I., Hajime Kishi et al, Mokuzai Gakkaishi, 1988, Vol. 34, No. 2, pp. 133-139. 22 Filed: Oct. 14, 1997 “Composites of Wood and Polypropylenes III.', Gyu-Seong Related U.S. Application Data Han et al., Mokuzai Gakkaishi, 1989, vol. 35, No. 12, pp. 1100-1104. 63 Continuation of application No. 08/779,688, Jan. 7, 1997, “Properties of Blends of Starch and Synthetic Polymers abandoned, which is a continuation-in-part of application Containing Anhydride Groups”, Utpal R. Vaidya et al., No. 08/476,192, Jun. 7, 1995, abandoned, which is a con tinuation-in-part of application No. 08/224,396, Apr. 7, Journal of Applied Polymer Science, 1994, vol. 52, pp. 1994, abandoned, which is a continuation of application No. 617-628. 07/938,364, Aug. 31, 1992, abandoned. “Composites of Polyvinyl Chloride-Wood Fibers. III: Effect of Silane as Coupling Agent”, B. V. Kokta et al., Journal of (51) Int. Cl. .................................................. B32B5/16 Vinyl Technology, Sep. 1990, vol. 12, No. 3, pp. 146-153. 52 U.S. Cl. .......................... 428/393; 428/326; 428/359; “Composites of Poly(Vinyl Chloride-Wood Fibers: II. 428/3614; 428/378; 428/425.1; 428/479.3; Effect of Chemical Treatment, B. V. Kokta et al., Polymer 428/479.6; 428/507 Composites, 1989. 58 Field of Search ..................................... 428/326, 359, “Performance of Hybrid Reinforcements in PVC Compos 428/36.1.4, 378,393, 425.1, 479.3, 479.6, ites: Part I-Use of Surface-Modified Mica and Wood Pulp 507 as Reinforcements”, Debesh Maldas et al., Journal of Test ing and Evaluation, Jan. 1993, vol. 21, No. 1, pp. 68-72. 56) References Cited Performance of Hybrid Reinforcements in PVC Compos U.S. PATENT DOCUMENTS ites: III. Use of Surface-Modified Glass Fiber and Wood Pulp as Reinforcements, D. Maldas et al., Journal of Rein 3,765,934 10/1973 Gaylord .................................. 117/148 forced Plastics and Composites, Oct. 1992, vol. II, pp. 3.869,432 3/1975 Gaylord ... ... 260/78.5 R 1093-1102. 3,894.975 7/1975 Gaylord ... 260/17.4 GC “Surface modification of wood fibers using maleic anhy 3,900,685 8/1975 Gaylord .................................. 428/420 dride and isocyanate as coating components and their per (List continued on next page.) formance in polystyrene composites', D. Maldas et al., J. Adhesion Sci. Technol., 1991, vol. 0, No. 0, pp. 1-14. FOREIGN PATENT DOCUMENTS “PMSE-Polymeric Materials Science and Engineering”, 2 104903 3/1983 United Kingdom. Spring Meeting 1992, San Francisco, CA, Proceedings of 2 192397 1/1988 United Kingdom. the American Chemical Society, Division of Polymeric OTHER PUBLICATIONS Materials: Science and Engineering, Vol. 66. Composites of Poly(Vinyl Chloride) and Wood Fibers. Part Primary Examiner Richard Weisberger II: Effect of Chemical Treatment, B. V. Kokta et al., Polymer Attorney, Agent, or Firm Merchant & Gould P.C. Composites, Apr. 1990, vol. 11, No. 2, pp. 84-89. 57 ABSTRACT “Wood Flour/Polypropylene Composites: Influence of Maleated Polypropylene and Process and Composition Vari The invention relates to a composite pellet comprising a ables on Mechanical Properties”, G. E. Myers et al., Intern. thermoplastic polymer and wood fiber composite that can be J. Polymeric Mater, 1991, vol. 15, pp. 21-44. used in the form of a linear extrudate or thermoplastic pellet “Effectiveness of Maleated Polypropylenes as Coupling to manufacture structural members. The fiber can be modi Agents for Wood Flour/Polypropylene Composites”, D. J. fied to increase compatibility. The polymer and wood fiber Olsen, ANTEC 91, pp. 1886–1891. composite may contain an intentional recycle of a waste “Toughened Thermoplastic Composite. I. Cross-Linkable Stream which can comprise adhesive, paint, preservative, or Phenol Formaldehyde and Epoxy Resins-Coated Cellulo other chemical waste Stream common in the wood-window sic-Filled Polypropylene Composites”, M. M. Sain et al., or door manufacturing process. The initial mixing Step Journal of Applied Polymer Science, 1993, vol. 48, pp. before extrusion of the composite material insures Substan 2181-2196. tial mixing and melt contact between molten polymer and “The Efficiency of Cellulosic Fillers in Common Thermo Wood fiber. The extruded pellet comprises a consistent plastics. Part II. Filling with Processing Aids and Coupling proportion of polymer, wood fiber and water. Agents”, H. Dalvaget al., Intern J. Polymeric Mater, 1985, vol. 11, pp. 9-37. 9 Claims, No Drawings 5,981,067 Page 2 U.S. PATENT DOCUMENTS 4,717,742 1/1988 Beshay .................................... 523/203 3,943,0792 - - -2 3/1976 Halled d . 260/17.4 BB 4,752,526 6/1988 Daimon et al. ......................... 428/332 3,958,069 5/1976 Gaylord .................................. 428/407 4.820,749 4/1989 Beshay - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 523/203 4,051,214 9/1977 Casper et al. .. ... 264/137 5,120,776 6/1992 Raj et al. .................................. 524/13 4,414,267 11/1983 Coran et al. ... 428/288 5,153,241 10/1992 Beshay ........................................ 524/8 4,528.303 7/1985 Segaud .................................... 523/212 5,288,772 2/1994 Hon ........................................... 524/35 5,981,067 1 2 ADVANCED COMPATIBLE POLYMER components. Thermoplastic materials Such as polyvinyl WOOD FIBER COMPOSITE chloride have been combined with wood members in manu facturing PERMASHIELD(E) brand windows manufactured “This application is a Continuation of application Ser. by AnderSen Corporation for many years. The technology No. 08/779,688, filed Jan. 7, 1997, now abandoned, which disclosed in Zanini, U.S. Pat. Nos. 2,926,729 and 3,432,883, application(s) is a divisional application of Ser. No. 08/476, have been utilized in the manufacturing of plastic coatings 192, filed Jun. 7, 1995, now abandoned, which is a or envelopes on wooden or other Structural members. continuation-in-part application of U.S. Ser. No. 08/224, Generally, the cladding or coating technology used in mak 396, filed Apr. 7, 1994, now abandoned, which is a continu ing PERMASHIELD(R) windows involves extruding a thin ation application of U.S. Ser. No. 07/938,364, filed Aug. 31, polyvinyl chloride coating or envelope Surrounding a 1992, now abandoned, which application(s) are incorporated Wooden Structural member. herein by reference.” Recent advances have made a polyvinyl chloride/ cellulosic fiber composite material useful in the manufacture FIELD OF THE INVENTION of Structural members for windows and doors. Puppin et al., 15 U.S. Pat. No. 5,406,768 comprise a continuous phase of The invention relates to compatible composite thermo polyvinyl chloride and a particular wood fiber material plastic materials used for the fabrication of Structural mem having preferred fiber size and aspect ratio in a thermoplas bers. The thermoplastic materials comprise a continuous tic material that provides engineering properties for Struc phase of polyvinyl chloride having a discontinuous phase of tural members and for applications in window and door a cellulosic fiber. The composite material is maintained manufacture. These thermoplastic composite materials have thermoplastic throughout its useful life by avoiding the use become an important part of commercial manufacture of of any Substantial concentration of crosslinking agents that window and door components. While these materials are would either crosslink cellulosic fibers, polymer molecules Sufficiently Strong for most structural components used in or cellulosic fiber to polymer. The physical properties of the thermoplastic material are improved by increasing polymer window and door manufacture, certain components require 25 added Stiffness, tensile Strength, elongation at break or other fiber compatibility, i.e. the tendency of the polymer and fiber engineering property not always provided by the materials to mix. The improved mixing tendencies improves the disclosed in Puppin et al. coatability of the fiber by polymer, increases the degree the We have examined the modification of thermoplastic polymer wets the fiber in the melt Stage and Substantially materials in the continuous polymer phase, the modification increases the engineering properties of the materials as a of the cellulosic materials in the discontinuous cellulosic whole. In particular, the improved engineering properties phase for improving the Structural polymers of these com include increased tensile Strength when compared to posite materials. The prior art has recognized that certain immodified