摘要
采用在熔融挤出过程中提高双螺杆挤出机螺杆转速的高剪切应力诱导方法,研究了双螺杆挤出机的螺杆转速和挤出反应温度对脱硫轮胎胶共混物(DGTR-EPDM)凝胶含量、溶液特性黏数和溶胶红外吸收光谱的影响.研究了脱硫工艺条件对丁苯橡胶-脱硫轮胎胶共混物(SBR-DGTR-EPDM)再硫化共混材料力学性能的影响.实验结果表明:双螺杆挤出机的高剪切应力作用,可诱发废旧轮胎胶粒(GTR)中交联网络的断链反应和氧化降解作用,引起脱硫共混物(DGTR-EPDM)中凝胶含量的下降、溶液特性黏数的减小和溶胶分子链中含氧基团和亚磺酸酯基团的明显增加.挤出机螺杆转速越快,挤出反应温度越高,其所得SBR-DGTR-EPDM再硫化共混材料中未脱硫凝胶颗粒尺寸即越小.在最佳脱硫反应条件下,所得DGTR-EPDM-SBR再硫化共混材料的拉伸强度和断裂伸长率分别达到19.5 MPa和400%.
The effect of high shearing stress of the twin screw extruder during melt extruding on the gel content and the sol intrinsic viscosity of the devulcanized blends （ DGTR - EPDM） and FT-IR spectra of their sol were investigated by increasing the screw rotation speed and reaction temperature, and the influence of the devulcanization conditions on the mechanical properties of styrene-butadiene rubber （ SBR - DGTR - EPDM） revulcanized blends was studied. The results showed that the high shearing stress of the twin screw extruder during melt extruding could induce chain scission and oxidative degradation of the cross-linking network of the ground tire rubber （GTR） , which obviously increased ester bond and sulfinoacid ester group in the sol of the devulcanized blends. As a result, the gel content and the sol intrinsic viscosity of the devulcanization blends were decreased. The size of gel grain in SBR - DGTR- EPDM revutcanized blends decreased with increasing the screw rotation speed and the reaction tempera- ture. Under the optimum conditions, the tensile strength of the revulcanized blend was 19. 5 MPa and its elongation at break reached to 400%.
出处
《南京工业大学学报（自然科学版）》
CAS
2008年第1期69-73,共5页
Journal of Nanjing Tech University(Natural Science Edition)
关键词
轮胎胶
高剪切应力
脱硫
EPDM
SBR
ground tire rubber
high shear stress
devulcanization
EPDM
SBR
