聚对苯二甲酸丁二醇酯塑料颗粒PA/PC/PBT合金材料GF30 GF15颗粒PBT GF35 V0Polybutylene Terephthalate Plastic Pellets PA/PC/PBT Alloy Material GF30 GF15 Granules PBT GF35 V0