用同向双螺杆挤出机制备液体脱硫橡胶

Preparation of liquid devulcanized rubber in a co-rotating twin-screw extruder

采用双螺杆挤出机将废胶粉进行连续脱硫以制备溶胶含量较高的脱硫橡胶,脱硫橡胶可呈流体状态。影响脱硫效果的工艺因素主要有螺杆转速、机筒温度、废胶粉的粒径以及添加剂的用量。对脱硫橡胶进行了溶胶含量、门尼黏度、凝胶渗透色谱及差示扫描量热等的测试分析,结果表明,提高螺杆转速会降低橡胶的溶胶含量,升高机筒温度可以有效提高橡胶的溶胶含量,胶粉粒径越大制得的脱硫橡胶的溶胶含量越低,增加脱硫剂的用量可以提高橡胶的溶胶含量。通过温度、螺杆转速和添加剂用量的选择可以得到脱硫程度不同的脱硫橡胶。

The liquid devulcanized rubber was prepared with ground tire rubber as raw material by continuous devulcanization in a co-rotating twinscrew extruder,and the influence factor,such as screw speed,barrel temperature,size of ground tire rubber and amount of additives,were investigated.The sol content and Mooney viscosity were measured and the obtained devulcanized rubber was characterized by gel permeation chromatography and differential scanning calorimetry. The results showed that increasing screw speed decreased sol content in devulcanized rubber,but raising barrel temperature increased it effectively. The larger the size of ground tire rubber,the smaller the sol content in devulcanized rubber,and with increasing amount of desulfurizer,the sol content was improved. The devulcanized rubbers with different sol contents could be prepared at different barrel temperatures, screw speeds and additive amounts.