干喷湿纺法制备T700级聚丙烯腈基碳纤维

采用丙烯腈、氨化试剂A、丙烯酸甲酯为聚合单体,以偶氮二异丁腈为引发剂,在溶剂二甲基亚砜中合成了聚丙烯腈原丝纺丝液,经干喷湿纺法纺丝制得聚丙烯腈原丝,经预氧化和炭化得到了T700级高性能聚丙烯腈基碳纤维。采用扫描电子显微镜,差示扫描量热仪,电子万能材料试验机对纤维的性能进行了研究。研究了空气层距离、喷丝头长径比、凝固浴浓度、空气拉伸比对干喷湿纺法制备纤维性能的影响。在空气层距离为40mm、凝固浴浓度为70%、喷丝头长径比为10.0、空气拉伸比为1.8条件下,采用干喷湿纺法制得的T700级聚丙烯腈基原丝及碳纤维的表面光滑、无沟槽,截面形貌为圆形;原丝的拉伸强度可达8.7cN/dtex,拉伸弹性模量可达154.7cN/dtex,碳纤维的拉伸强度可达5 750MPa,拉伸弹性模量可达220GPa。

Preparation of T700 Grade PAN Carbon Fiber by Dry Spray Wet Spinning

The polyacrylonitrile (PAN) spinning solution was synthesized by the monomer acryonitrile,ammoniation regent A,and methyl acrylate with dimethyl sulfoxide as solvent and azodiisobutyronitrile for initiator,and PAN carbon fiber precursor was prepared by dry spray wet spinning. T700 grade high performance PAN carbon fiber was prepared by preoxidtion and carbonization. The properties of PAN carbon fiber were studied by scanning electron microscope,differential scanning calorimeter and electronic universal material tester. The effects of the air layer distance,the length and diameter ratio of spinneret,the cogulation bath concentration and the air drawing ratio on the properties of PAN carbon fiber prepared by dry spray wet spinning were studied. When the air layer distance is 40mm,the length and diameter ratio of spinneret is 10.0,the coagulation bath concentration is 70% and the air drawing ratio is 1.8,the surface of PAN carbon fiber is smooth without grooves,the cross section of the PAN precursor and carbon fiber are circular,the tensile strength of PAN precursor can reach 8.7cN/dtex,the tensile elastic modulus of PAN precursor can reach 154.7 cN/dtex,the tensile strength of PAN carbon fiber can reach 5 750 MPa and the tensile elastic modulus of PAN carbon fiber can reach 220 GPa.