Abstract: Members including components of windows and doors are formed by a method that includes obtaining a biopolymer and a filler, feeding them into an extruder, controlling at least the temperature of the biopolymer and the filler within the extruder to promote the initiation of nucleation of the biopolymer, extruding the composite through a die of the extruder to form an extruded member and controlling at least the cooling rate of the extruded member after it leaves the die to promote crystallization of the biopolymer. Methods are disclosed for compounding and pelletizing as well as direct extrusion of the composite. In a preferred embodiment, the biopolymer is polylactic acid (PLA) and the filler is wood fiber. In addition, neat PLA formulations are also disclosed. Further, the heat distortion temperature and the hydrolysis resistance of these members are greatly increased through specific processing conditions and the addition of strategic quantities of additives.

Abstract: Members including components of windows and doors are formed by a method that includes obtaining a biopolymer and a filler, feeding them into an extruder, controlling at least the temperature of the biopolymer and the filler within the extruder to promote the initiation of nucleation of the biopolymer, extruding the composite through a die of the extruder to form an extruded member and controlling at least the cooling rate of the extruded member after it leaves the die to promote crystallization of the biopolymer. Methods are disclosed for compounding and pelletizing as well as direct extrusion of the composite. In a preferred embodiment, the biopolymer is polylactic acid (PLA) and the filler is wood fiber. In addition, neat PLA formulations are also disclosed. Further, the heat distortion temperature and the hydrolysis resistance of these members are greatly increased through specific processing conditions and the addition of strategic quantities of additives.