超微细碳酸钙的复合改性及其在LDPE上的应用研究

Study on the Composite Modification of Ultrafine Calcium Carbonate and the Application in LDPE

研究了硬脂酸与DL-411铝酸酯偶联剂混合对超微细CaCO3的湿法改性及其对LDPE的填充效果。通过硬脂酸和DL-411铝酸酯分别单独改性碳酸钙,测定活化指数,确定最佳改性剂用量为2%,然后按不同配比的硬脂酸和DL-411铝酸酯混合改性CaCO3,结果表明当硬脂酸用量为1.5%、DL-411铝酸酯用量为0.5%时,对碳酸钙具有最佳改性效果:活化指数99.71%、吸油值46.19mL/100g、最终的沉降体积2.3mL/g、10g改性碳酸钙与100mL液体石蜡混合物的黏度4.4Pa.s。将改性碳酸钙填充到LDPE中,当改性CaCO3含量为10%时,复合材料具有较好的力学性能。

The CaCO3 modified with the mixture of stearic acid and DL-411 aluminate coupling agent, and effects of LDPE filled with it were studied. The CaCO3 was modified respectively by stearic acid and DL-411 aluminate coupling agent. The results showed that the 2 % amount of modifying agent alone had the best effect. When the amount of stearic acid was 1.5 % and DL-411 aluminate was 0.5 %, the results had the excellent effects, which the activation exponential was 99.71%, the oil absorption number was 46.19 mL/100 g, the sedimentation volume was 2.3 mL/g and the viscosity （10g CaCO3/100 mL liquid paraffin） was 4.4 Pa＇s. Filled with the modified calcium carbonate, when the amount of modified CaCO3 was 10 %, the samples of LDPE had better mechanical properties.