论文题目：快速结晶PET/PEN共混材料的制备及性能研究

 

毕业学生：吴仁

 

指导教师：吴唯

 

中文摘要：

     本文以NaHCO₃、苯甲酸钠和高分子离子聚合物（Surlyn）作为成核剂，研究其对PET/PEN共混材料性能的影响。制备了能够快速结晶的性能优良的PET/PEN/Surlyn共混材料以满足工程领域应用。采用差示扫描量热仪（DSC）、X射线衍射仪（XRD）、偏光显微镜（POM）研究了PET/PEN/成核剂共混材料的结晶性能；采用万能试验机和冲击试验机研究了共混材料的力学性能；采用热变形维卡软化点试验机和热重分析仪（TGA）研究了共混材料的热性能。通过对共混物结晶性能、力学性能和热性能的测试，研究了不同成核剂对PET/PEN共混物结晶增强机理。

实验结果表明三种成核剂均能显著提高共混物的结晶能力，其中，Surlyn和苯甲酸钠能明显提高共混物结晶性能，结晶峰温度提高约20℃，结晶速度明显加快。三种成核剂中，唯有Surlyn在提高结晶性能的同时，还能提高共混材料的力学性能。Surlyn是PET/PEN共混物理想的成核剂。

对PET/PEN/Surlyn共混物加工工艺和各组分配比研究表明，加工工艺对共混物结晶性能影响不大，但共混时间较共混温度对共混物结晶性能影响明显。PEN含量的增加会提高共混物拉伸性能和弯曲性能，但是使得共混物的结晶性能和冲击性能降低。适量添加Surlyn，能促进PET/PEN共混物的成核结晶，明显提高结晶速度、结晶温度和结晶度，能减小球晶尺寸，提高球晶均匀性，并有助于改善PET和PEN相容性，从而提高PET/PEN共混材料的拉伸强度、弯曲强度、弯曲模量和缺口冲击强度等力学性能。过量Surlyn的加入反而会损害共混物的结晶性能、力学性能和热性能。本研究体系Surlyn的最佳用量为2 phr。

  Abstract:

       In this paper，sodium bicarbonate，sodium benzoate and ethylene methacrylic acid ionomer（Surlyn）were added to PET/PEN blends to improve the crystallization and mechanical properties of PET/PEN/ Nucleation agents blends. Differential Scanning Calorimetry（DSC），X-Ray Diffraction（XRD）and polarizing microscope（POM）were used to characterize the crystallization properties. The mechanical and thermal properties of PET/PEN blends were investigated by mechanical tester，vicat softening point tester and thermal gravimetric analysis（TGA）. The crystallization and strengthening mechanism of PET/PEN/ Nucleation agents blends were also studied through the crystallization，mechanical and thermal properties test.

    The results showed that all the nucleation agents promoted the nucleation properties of PET/PEN blends. The crystallization peak temperature was increased nearly 20℃ and the crystallization rate was also improved due to the addition of sodium benzoate and Surlyn. With the addition of Surlyn，both of the crystallization and mechanical properties were improved. The ideal nucleation agent of PET/PEN blends was Surlyn.

The blending processes and component contents of PET/PEN/Surlyn blends were also studied. The results showed that the blending processes didn’t have a big effect on the crystallization properties of the blends. With the increasing to PEN contents，the tensile properties and flexural properties improved while the impact strength and crystallization properties declined. With proper Surlyn addition，the nucleating and crystallization ability of PET/PEN blends were promoted，and the crystallization rate，crystallization temperature，crystallinity and spherulite uniformity were improved while spherulite size decreased. The compatibility of PET and PEN was improved and the mechanical properties（tensile strength，flexural strength，flexural modulus and notched impact strength）of PET/PEN blends were enhanced due to the addition of Surlyn. The best properties were achieved when the mass content of Surly was 2 phr in this study.

  

论文题目：导电型聚苯胺及聚丙烯/聚苯胺抗静电材料的制备与性能研究

 

毕业学生：骆巧玲

 

指导教师：吴唯

 

中文摘要：

本文选用对甲基苯磺酸（TSA）掺杂聚苯胺（PANI），最终获得具有最大电导率（0.096S/cm）的PANI-TSA的反应条件，即掺杂时间为12h，TSA浓度为0.5mol/L，掺杂温度为25℃。对加工工艺进行探索，得到PP/PANI-TSA的最佳加工工艺为：采用密炼共混，加工温度为195℃，转速为60rpm，加工时间为5min。

探究了PANI-TSA:SDBS（十二烷基苯磺酸钠）质量比和PANI-TSA含量对PP/PANI-TSA性能的影响。结果表明：随着SDBS质量比的增大，PP/PANI-TSA体系的电阻率减小，体系的介电常数增大了5个数量级，出现介电松弛现象，介电损耗峰对应的频率越大；当PANI-TSA:SDBS=1:2时，体系达到最低的熔融温度（164℃）和结晶温度（116℃），最高的热分解温度（464℃）；PP的结晶度随SDBS质量比的增大而减小，当PANI-TSA:SDBS=1:4时，PP的结晶度达到最小（37.6%）；体系的力学性能严重下降，拉伸强度下降57.96%，弯曲强度下降57.43%。体系的流动性能变好，平衡扭矩值减小44%。

探究PANI-TSA含量的影响结果表明：PANI-TSA含量为10%达到了渗流阈值，形成了导电网络，从而导致电阻率的突变为4.42×107Ω•cm-1，PP的最大分解温度提高了15℃。随着PANI-TSA含量的增加，体系的熔融温度未发生明显变化，PP的结晶度保持40%不变；体系的力学性能严重下降；体系的MFR增大，最大扭矩峰出现的时间延迟，平衡扭矩值减小。

综上所述，当PANI-TSA:SDBS=1:2，PANI-TSA含量为10%时，PP/PANI-TSA综合性能最好。

 Abstract：

    In this paper, TSA as a dopant doped PANI, the optimal reaction conditions were received with the doping time of 12hr, the TSA concentration of 0.5mol/L and the temperature of 25℃. PP was mixed with PANI-TSA in a Hapro rheometer at 195℃, shear rate of 40rpm and mixing time of 5min.

The influence of the mass ratio of PANI-TSA and SDBS and PANI-TSA contents on the performance of PP/PANI-TSA of anti-static materials was explored. The results showed that with SDBS contents increasing, the resistivity of blends decreased, and the dielectric constant increased by 105, and the blends showed relaxtion phenomenon and the frequency with appearance of loss peak increased. When the mass ratio of PANI-TSA was 1:2, the blends showed the lowest melt temperature of 164℃ and crystallization temperature of 116℃, and the highest decomposition temperature of 464℃. The crystallinity of blends decreased as the SDBS contents increased. At last, SDBS damaged seriously the mechanical properties of PP/PANI-TSA, the tensile strength dropped by 57.96% and the flexural strength was downed by 57.43%. That the balance torque decreased by 44% showed the blends had the good rheological performance.

The exploration of the affect of the PANI-TSA contents on the blends showed when PANI-TSA contents was 10%, the resistivity of blends swooped to 4.42×107Ω•cm-1, and the decomposition temperature of blends rose by 15℃.That meaned the percolation threshold of PANI-TSA was 10%. As the PANI-TSA contents raised, the melt temperature and crystallinity of PP/PANI-TSA didn’t change, PANI-TSA harmed seriously the blend’s mechanical properties.

    In a word, PP/PANI-TSA showed the best performance with the mass ratio of PANI-TSA and SDBS of 1:2, and the PANI-TSA contents of 10%