各种扩链剂对PET瓶片反应挤出扩链作用的研究

Study on Chain Extension of PET Flakes by Reactive Extrusion with Chain Extenders

分别采用甲苯二异氰酸酯、三氧化二锑、邻苯二甲酸酐、均苯四酐、萘四甲酐以及均苯四酐和邻苯二甲酸酐混合物作为聚对苯二甲酸乙二醇酯(PET)瓶片的扩链剂,研究了反应挤出后产物特性黏度的变化。结果表明,甲苯二异氰酸酯、三氧化二锑、邻苯二甲酸酐和萘四甲酐对PET瓶片的扩链效果较弱;均苯四酐可明显提高PET的特性黏度。均苯四酐和邻苯二甲酸酐复配后的扩链效果最为显著;当均苯四甲酸二酐用量为0.3%、邻苯二甲酸酐用量为0.2%时,PET的特性黏度达到0.96dL/g。

The chain extension of recycled PET flakes was studied via reactive extrusion using diisocyanatotoluene （TDI）, antimony trioxide （ Sb2O3 ）, phthalic anhydride, pyromellitic dianhydrde （PMDA）, and naphthalenetetra carboxylic dianhydride （NTDA） as chain extenders. It was found that effects of TDI, Sb2Oa, phthalic anhydride and NTDA were weak, while PMDA could increase the intrinsic viscosity of the material obviously. A mixture of PMDA and phthalic anhydride provided the best chain extension. The intrinsic viscosity of the material reached 0. 96 dL/g when the content of PMDA and phthalic anhydride was 0.3 % and 0. 2 %, respectively.