高密度聚乙烯三维网状纳微米纤维的强伸性能

Tensile properties of high-density polyethylene nano-micron fibers with three-dimensional network structure

为实现高密度聚乙烯三维网状纳微米纤维(PENFs)的自主化规模化生产,以高密度聚乙烯和二氯甲烷为原料,通过高压闪喷纺丝设备成功制备了性能优异的PENFs,采用响应面法对纺丝过程中各工艺参数进行优化,并对其力学性能和耐候性能进行分析。结果表明:PENFs的最佳制备工艺条件为纺丝温度176.3℃、纺丝压力8.6 MPa、纺丝溶液质量分数8.0%,此时制得的PENFs的断裂强度和断裂伸长率分别可达到29.1 cN/dtex和99.9%,优于芳纶和涤纶等常规纤维;定伸长和定载荷条件下,PENFs的弹性回复能力随着拉伸次数和载荷的增加而逐渐降低,拉伸伸长为5%时PENFs纤维的弹性回复率可达到92.8%且拉伸10次后降低至75.5%,拉伸载荷为1.2 N时PENFs纤维的弹性回复率为84.6%;放置在室外20 d内PENFs纤维的强伸性能损失较小,30 d后断裂强度和断裂伸长率明显降低,但纤维外貌并无明显变化。

In order to achieve the large-scale production of high-density polyethylene nano-micron fibers with three-dimensional network(PENFs),high-density polyethylene and dichloromethane were used as raw materials,PENFs with high-performance were successfully prepared by high-pressure flash spinning equipment.The parameters during spinning process were optimized by response surface methodology.The mechanical and weather resistance properties of PENFs were analyzed.The results showed that the optimal preparation conditions for PENFs are spinning temperature of 176.3℃,spinning pressure of 8.6 MPa,and spinning solution mass fraction of 8.0%,then the fracture strength and elongation at break of the prepared PENFs can reach 29.1 cN/dtex and 99.9%,respectively,which are superior to conventional fibers such as aramid and polyester.Under constant elongation and load conditions,the elastic recovery ability of PENFs decreases gradually with the increase of stretching times and load.When the stretching elongation is 5%,the elastic recovery rate of PENFs fibers can reach 92.8%,then decrease to 75.5%after stretching 10 times.When the stretching load is 1.2 N,the elastic recovery rate of PENFs fibers is 84.6%.The strength and elongation of PENFs fibers have little loss when PENFs fibers are placed outdoors for 20 d,and after 30 d the fracture strength and elongation at break of PENFs fibers significantly decrease,but there is no significant change in the appearance of the fibers.