碳纳米管-炭黑协同改性PTT/PET复合纤维的制备及导电性能

聚对苯二甲酸丙二醇酯/聚对苯二甲酸乙二醇酯(PTT/PET)复合纤维具有稳定且高度螺旋的卷曲结构,为改善其抗静电性能,采用碳纳米管(CNT)/炭黑(CB)复合填料对PTT进行共混改性。将不同质量比的CNT,CB及PTT共混挤出,制备出用于纺丝的CNT/CB/PTT共混切片,CNT/CB/PTT共混切片与PET切片复合纺丝制备CNT-CB协同改性PTT/PET复合纤维,并对复合纤维的导电性能进行表征。结果表明:采用质量分数1%的CNT和质量分数10%的CB作为导电填料对PTT改性,导电粒子在PTT基体中未出现明显的团聚,且CNT和CB可以形成较为完善的复合导电通路,制备的CNT/CB/PTT共混切片可用于纺丝;将CNT/CB/PTT共混切片与PET切片按质量比50∶50进行复合纺丝,制得的复合纤维具有良好的导电性能;随拉伸倍数的提高,复合纤维的体积电阻率呈下降趋势,但拉伸倍数过高,会损坏CB与CNT在PTT基体中形成的导电网络,当拉伸倍数为3. 3时,未改性的PTT/PET复合纤维体积电阻率为3. 58×10~9Ω·cm,而改性复合纤维的体积电阻率下降至5. 44×10~6Ω·cm。

Preparation and electrical conductivity of carbon nanotube-carbon black modified PTT/PET composite fiber

Polypropylene terephthalate/polyethylene terephthalate(PTT/PET)composite fiber possesses a stable and highly spiral crimp structure.The composite filler of carbon nanotube(CNT)and carbon black(CB)was used in the blend modification of PTT in order to improve its antistatic property.CNT,CB and PTT were blended and extruded at different mass ratio to prepare a CNT/CB/PTT blend chip which was spun with PET chip and produced into a CNT-CB modified PTT/PET composite fiber via composite spinning process.The electrical conductivity of the obtained composite fiber was characterized.The results showed that the conductive particle did not obviously agglomerate in PTT matrix,CNT and CB formed a fairly good composite conductive path and the prepared CNT/CB/PTT blend chip can be used for spinning when 1%CNT and 10%CB by mass fraction were used as the conductive filler in the modification of PTT;the produced composite fiber exhibited fairly good conductivity when the CNT/CB/PTT blend chip was blended with PET chip at the mass ratio of 50 50 via composite spinning;the volume resistivity of the composite fiber appeared a downward tendency when the draw ratio was increased;however,the extremely high draw ratio would damage the conductive network of CB and CNT in PTT matrix;and the unmodified PTT/PET composite fiber had the volume resistivity of 3.58×10^9Ω·cm and the volume resistivity of the modified composite fiber was decreased to 5.44×10^6Ω·cm at the draw ratio of 3.3.