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取代芳基磷酸金属盐类成核剂对聚乳酸结晶的影响 总被引:7,自引:0,他引:7
通过示差扫描量热仪(DSC)和偏光显微镜(POM)考察了取代芳基磷酸金属盐类成核剂对聚乳酸结晶行为的影响。结果表明:取代芳基磷酸一价盐和三价盐可以较好的改善聚乳酸的结晶,其中取代芳基磷酸锂盐的效果最好,使结晶温度提高了4℃。取代芳基磷酸二价盐对于聚乳酸结晶的改善并不明显。对取代芳基磷酸金属盐类成核剂浓度效应的研究发现:1%为其在聚乳酸中的饱和添加浓度。针对滑石粉和取代芳基磷酸锂盐进行了复配研究,发现复配后的成核剂可以更好的促进聚乳酸的结晶。 相似文献
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《工程塑料应用》2020,(8)
制备了一类新型高分子型聚丙烯酸盐类成核剂。通过分子量为300万~700万的聚丙烯酸钠分别与氯化钡、氯化钙和氯化锌进行反应,制得了聚丙烯酸钡、聚丙烯酸钙和聚丙烯酸锌三种成核剂,通过傅立叶变换红外光谱仪、X射线光电子能谱分析仪表征合成产物的结构。利用差示扫描量热仪分析了成核剂对等规聚丙烯(iPP)成核效果的影响,结果表明,在制备的三种聚丙烯酸盐成核剂中,聚丙烯酸钡能够明显提高iPP的结晶峰温度。同时,研究了聚丙烯酸钡成核剂在iPP中的最佳添加量,发现聚丙烯酸钡添加量为0.3%时,改性iPP的结晶峰温度比空白iPP增加了6.5℃。非等温结晶动力学研究结果表明,加入聚丙烯酸钡成核剂没有改变iPP结晶的生长方式。综合来看,聚丙烯酸钡是一种优良的iPP α成核剂。 相似文献
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复配型结晶成核剂对PET结晶行为的影响 总被引:1,自引:0,他引:1
制备了以聚对苯二甲酸乙二醇酯(PET)为基体的复配型PET结晶成核剂母料——Nu-1;利用12SC研究了不同添加量的Nu-1对PET结晶行为的影响;对比了该成核剂与科莱恩公司的101和杜邦公司的Surlyn对PET结晶行为的影响。结果表明:Nu-1的加入可以有效促进PET结晶的成核速率,随着添加量从2%升高到5%,PET的结晶速率明显提高。在添加量相同时,Nu-1对PET结晶的促进作用接近101和Surlyn。 相似文献
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研究了二环[2.2.1]庚烷二羧酸盐成核剂(商品名:HPN-68)对聚丙烯(PP)结晶行为和力学性能的影响。结果表明:HPN-68是一种典型的聚丙烯α晶型成核剂,在PP中具有很高的成核效率。在较低的添加浓度下可明显提高PP的结晶峰温度和力学性能。然而,其添加量存在一个饱和值。当成核剂含量达到该饱和值以后,PP的结晶峰温度和力学性能就趋于稳定。当成核剂HPN-68的添加量为0.2 phr时,PP的结晶峰温度可升高15℃左右,拉伸强度和弯曲模量分别可提高12.7%和18.2%。 相似文献
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利用偏光显微镜(PLM)、光电雾度仪、差热分析(DSC)及力学性能测试考察有机磷酸盐(NA-21)与硅溶胶复配成核荆对均聚聚丙烯(PP)透明性、结晶行为及力学性能的影响.研究结果表明:有机磷酸盐与硅溶胶有良好的协同异相成核作用;复配体系中,纳米微粒的分散性明显好于添加单一纳米成核剂的分散性;硅溶胶的添加量为0.15%,有机磷酸盐的添加量为0.35%时,成核PP的雾度降低到36.3%,结晶温度升高到132℃;与单-NA-21增透PP相比,复配成核荆增透PP的冲击强度与拉伸强度都有明显提高. 相似文献
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采用DSC、WAXD、PLM等分析手段研究了辛二酸和辛二酸盐对等规聚丙(烯iPP)结晶行为的影响。结果表明:辛二酸、辛二酸锂、辛二酸钠、辛二酸钾、辛二酸镁、辛二酸钡和辛二酸锌都不是β晶成核剂,辛二酸锶和辛二酸镉是弱β晶成核剂,辛二酸钙是强β晶成核剂。通过分析结晶温度发现,辛二酸和辛二酸盐对iPP成核能力的大小顺序为:辛二酸>辛二酸钙>辛二酸镁>辛二酸锌>辛二酸钾>辛二酸镉>辛二酸钡>辛二酸钠>辛二酸锶>辛二酸锂。 相似文献
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将α成核剂六氢邻苯二甲酸钙和β成核剂六氢邻苯二甲酸锌复合得到α/β复合成核剂体系,研究了其对等规聚丙烯(iPP)力学性能和结晶性能的影响,并用Avrami理论研究了成核iPP的等温结晶动力学。结果表明,α/β复合成核剂以特定比例复合可以同时提高iPP的刚性和韧性,其中在复合比例为7∶3时,拉伸强度提升了6.7 %,弯曲模量提升了21.8 %,冲击强度提升了108.2 %。进一步研究了复合成核剂在iPP中的浓度效应,随着总添加量的增加,iPP的结晶温度逐渐增加,力学性能趋于稳定,在添加量达到0.4 %(质量分数,下同)时基本不变,此时冲击强度提升了175.3 %,弯曲模量提升了15.0 %,拉伸强度提升了6.5 %。等温结晶动力学的结果表明,复合成核剂体系的加入可以明显缩短iPP的结晶时间并且降低结晶所需的表面能。 相似文献
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Kyung Su Kang Sang Il Lee Tae Jin Lee Ramani Narayan Boo Young Shin 《Korean Journal of Chemical Engineering》2008,25(3):599-608
The effect of chemically modified thermoplastic starch (CMPS) on the thermal properties and isothermal crystallization kinetics
of poly(lactic acid) (PLA) was studied by differential scanning calorimetry (DSC) and compared to that of granular starch
and an inorganic nucleating agent, talc. Nucleated PLA showed an additional crystallization of PLA, which affected the melting
temperature. The crystallinity and crystallization rate of PLA were considerably enhanced by addition of CMPS, even at 0.1%
content, and the amount of the CMPS had little effect on the thermal properties and isothermal crystallization kinetics of
PLA. The effect of CMPS as a nucleating agent was comparable to that of granular starch but slightly less than that of talc.
However, CMPS can offer a fully biodegradable nucleating agent with no residues remaining for the biobased and biodegradable
polymers. 相似文献
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Effect of nucleation and plasticization on the stereocomplex formation between enantiomeric poly(lactic acid)s 总被引:1,自引:0,他引:1
The effect of nucleation and plasticization on the stereocomplex formation between poly(l-lactic acid) (PLLA) and poly(d-lactic acid) (PDLA) was investigated in blends where PDLA is added as a minor phase in a major phase of PLLA. The use of small amounts of PDLA is aimed at creating a high melting point stereocomplex phase that in turn can serve as nucleating agent for the major phase of PLLA. Blends containing 5% PDLA with talc or organic phosphonate as nucleants and polyethylene glycol as plasticizer were prepared via melt-blending. Their crystallization behavior was investigated through Differential Scanning Calorimetry (DSC) using various thermal histories. Two peculiar stereocomplex melting endotherms were found. The peak temperature and enthalpy of these two endotherms were correlated to prior isothermal crystallization temperature. The different endotherms were also associated with two different crystalline morphologies observed by optical microscopy and referred to as Network and Spherulitic morphologies. The influence of plasticization and of heterogeneous nucleation on these morphologies was investigated through optical microscopy and calorimetric observations. 相似文献
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Ping Song Guangyi Chen Zhiyong Wei Ying Chang Wanxi Zhang Jicai Liang 《Polymer》2012,53(19):4300-4309
A nanoscaled zinc citrate complex (ZnCC) was synthesized by the reaction of zinc acetate and citric acid using solution method. As a new eco-friendly nucleating agent, ZnCC was introduced into poly(l-lactic acid) (PLLA) via melt blending. The nonisothermal and isothermal crystallization, melting behavior, crystalline morphology and mechanical properties of the PLLA/ZnCC blends were investigated. It is found that ZnCC exhibits much more prominent nucleation activity on the crystallization of PLLA than conventional nucleating agent talc and commercial zinc citrate (ZnCit). By loading 0.05 wt% ZnCC, PLLA can complete crystallization upon cooling at 10 °C/min, and the crystallization peak shifts to a higher temperature with increasing ZnCC content. In the case of isothermal crystallization from the melt, the addition of ZnCC leads to a shorter crystallization time and a faster overall crystallization rate. Besides, the nucleation density of PLLA increases and the spherulite size decreases significantly in the presence of ZnCC. Epitaxy is the possible mechanism to elucidate the nucleation phenomenon of PLLA/ZnCC system. The tensile results show that ZnCC has a plasticization effect on the amorphous PLLA. Through a short-time annealing procedure, the mechanical properties such as tensile modulus and storage modulus of PLLA are improved by the addition of ZnCC. 相似文献
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采用DSC,POM研究了成核剂苯基磷酸锌(PPZn)对聚乳酸结晶行为的影响。结果表明:PPZn可以作为聚乳酸的高效成核剂,PPZn的加入显著提高了聚乳酸的结晶速率和结晶度。当PPZn的质量分数为5%0时TCs(起始结晶温度)降低了约24℃,TCe(终止结晶温度)降低了约29℃。PPZn的加入使聚乳酸的半结晶时间大大缩短。当PPZn的质量分数为2%时,结晶速率常数增大约5个数量级。 相似文献
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通过DSC考察了成核剂TMC-300对聚乳酸(PIA)成核结晶过程的影响,发现成核剂TMC-300可以有效地促进聚乳酸的成核结晶。在使用Avrami方程对该体系进行评价时发现,该方程只适应于聚乳酸结晶初期的评价,而在后期则出现严重偏离现象。 相似文献