In this paper, we report a technique for the surface modification of poly-(p-phenylene terephthamide)(PPTA) powder coated with polydopamine(PDOPA). We used air oxidation to self-polymerize dopamine(DOPA) to ensure tha...In this paper, we report a technique for the surface modification of poly-(p-phenylene terephthamide)(PPTA) powder coated with polydopamine(PDOPA). We used air oxidation to self-polymerize dopamine(DOPA) to ensure that the PPTA powder was coated. Our results indicate that the modified surface of PPTA powder enhances compatibility with the polymer matrix without damaging its structure. Additionally, it is possible to control the coating thickness of PDOPA by regulating the reaction time. The modified PPTA powder improved the comprehensive property of ethylene-propylene-diene-terpolymer grafted maleic anhydride(EPDM-g-MAH), and it proved that this method can enhance the strength and electric insulativity of EPDM-g-MAH.展开更多
The morphology of PPTA pulp is investigated by means of optical microscope and scanningelectron microscope (SEM). It shows that PPTA pulp has feather-like branch, needle point-likeend, and irregular cross-section, whi...The morphology of PPTA pulp is investigated by means of optical microscope and scanningelectron microscope (SEM). It shows that PPTA pulp has feather-like branch, needle point-likeend, and irregular cross-section, which are very important for PPTA pulp as a reinforcer. Theseparation limitation of PPTA pulp is also investigated from both torn and brittle break cross-sec-tion. A packing mechanism is proposed to illustrate the microfibril packing in the gel system.展开更多
High viscous PPTA copolymer is prepared by low temperature solution copolycondensation of terephth-aloylchloride, p-phenylenediamine and p, p'-diamino-phenylpiperazine in the NMP-CaCl2 solvent system. The inherent...High viscous PPTA copolymer is prepared by low temperature solution copolycondensation of terephth-aloylchloride, p-phenylenediamine and p, p'-diamino-phenylpiperazine in the NMP-CaCl2 solvent system. The inherent viscosity of all copolymers is more than 5. If more quantity of 3rd monomer is introduced into the macromolecular chain, the inherent viscosity becomes higher. The copolymer's ash content is less than 1000 μg/g. The heat durability of copolymer is close to that of PPTA, and its dissolubility is superior to that of PPTA.展开更多
基金supported by the National Natural Science Foundation of China (51273157)Program for New Century Excellent Talents in University (NCET-10-0659)Key Program of Natural Science Foundation of Hubei Province of China (2013CFA020)
文摘In this paper, we report a technique for the surface modification of poly-(p-phenylene terephthamide)(PPTA) powder coated with polydopamine(PDOPA). We used air oxidation to self-polymerize dopamine(DOPA) to ensure that the PPTA powder was coated. Our results indicate that the modified surface of PPTA powder enhances compatibility with the polymer matrix without damaging its structure. Additionally, it is possible to control the coating thickness of PDOPA by regulating the reaction time. The modified PPTA powder improved the comprehensive property of ethylene-propylene-diene-terpolymer grafted maleic anhydride(EPDM-g-MAH), and it proved that this method can enhance the strength and electric insulativity of EPDM-g-MAH.
文摘The morphology of PPTA pulp is investigated by means of optical microscope and scanningelectron microscope (SEM). It shows that PPTA pulp has feather-like branch, needle point-likeend, and irregular cross-section, which are very important for PPTA pulp as a reinforcer. Theseparation limitation of PPTA pulp is also investigated from both torn and brittle break cross-sec-tion. A packing mechanism is proposed to illustrate the microfibril packing in the gel system.
文摘High viscous PPTA copolymer is prepared by low temperature solution copolycondensation of terephth-aloylchloride, p-phenylenediamine and p, p'-diamino-phenylpiperazine in the NMP-CaCl2 solvent system. The inherent viscosity of all copolymers is more than 5. If more quantity of 3rd monomer is introduced into the macromolecular chain, the inherent viscosity becomes higher. The copolymer's ash content is less than 1000 μg/g. The heat durability of copolymer is close to that of PPTA, and its dissolubility is superior to that of PPTA.