碳酸钙填充聚乙烯的光老化性能研究

Studies on Photoaging Properties of Calcium Carbonate Filled Polyethylene

近年来国内外对以CaCO3为主的无机刚性粒子增强、增韧聚烯烃的基础和应用研究取得重大进展,填充的主要目的已从降低成本转向提高材料性能,展现出钙塑材料新的更广阔的应用前景。本文用人工光老化方法和红外光谱分析手段,对涉及材料使用寿命的光老化性能进行了研究,以期为这类钙材料的进一步推广应用提供更全面的理论和实际依据。 1 实验部分 1.1 主要原料 LDPE（北京燕山石化公司）:1F7B,MI=7。LLDPE（美国道化公司）:Dowlex 2037A,MI=2.4。CaCO3:四川雅安（A）、江油（B）产两种重质超细级产品,平均粒径分别为2.25和3.75μm。A的组成（％）:CaCO3>99.00,Fe2O3<0.07,Al2O3<0.12,MgO<0.10,SiO2<0.03;B的组成（％）:CaCO3>98.00,Fe2O3<0.12,Al2O3<0.36,MgO<1.40,SiO2<0.36。 受阻胺类光稳定剂,944FL（瑞士汽巴加基公司）,M>2500,记作F;GW-540（北京化工三厂）,M=541.8,记作G。 1.2 试样制备 按CaCO3:LDPE:PE蜡:钛酸酯=70:26:3:1（wt％）配比,将原料CaCO3在GH-10混合机中于2000r/min转速下用钛酸酯活化,加入PE蜡制得粉状复合物。后者与LDPE在SK-160B双辊炼塑机中于110℃混炼均匀,拉片切粒得CaCO3母粒（MB）。

Photoaging properties of calcium carbonate (CaCO3) filled polyethylene(PE) were investigated by means of artificial photoaging test. Photoaging qualities were characterized by the change of carbonyl concentration and double bond optical density with luminous flux with the aid of FTIR. It is showed that the photoaging behavior of CaCO3 filled plastics relates to metallic impurities in the filler, filler content, environment temperature etc.. Degradation with photoaging can be restrained by adding a little proper light stabilizer.