聚苯醚与尼龙6共混物的增容改性

以PPE／PA6共混物为基体,进行性能与结构的表征,对比了不同PPE／PA6比例的共混物性能以及添加增容改性树脂、增韧剂的使用效果。结果表明,增容改性树脂可使得PPE树脂粒子变得均匀,在提高共混材料的韧性的同时,改善了材料的拉伸性能;而弹性体虽可以提高PPE与PA6的共混物的冲击性能,但拉伸性能下降;添加5％增容改性树脂有助于改善玻纤增强PPE／PA6材料的力学性能。     

高阻隔高分子材料研究进展

介绍了高阻隔高分子材料的改性方法，包括共混与复配、多层复合、拉伸取向、表面处理和化学改性等，阐述了乙烯?乙烯醇共聚物（EVOH）、聚偏二氯乙烯（PVDC）、聚酰亚胺（PA）以及聚乙烯醇（PVA）等的性能特点及针对其阻隔性能等的改性研究进展。     

PA6含量对HDPE/PA6/MRP合金性能影响的研究

固定微胶囊化红磷（MRP）用量为11份,研究了不同尼龙6（PA6）含量对高密度聚乙烯（HDPE）／PA6／MRP合金阻燃性能、力学性能的影响,并用热重分析技术探讨了不同PA6含量时合金材料的残炭率、热降解起始温度。结果表明,当PA6含量为50份时,合金的阻燃性能、冲击强度及拉伸强度产生转变拐点,此时材料的冲击强度及残炭率最差。     

单环氧化合物接枝改性PA6材料的制备及其性能研究

利用反应挤出法制备了聚酰胺6（PA6）接枝新癸酸缩水甘油酯（GND）改性材料,通过红外光谱分析对改性产物的分子结构进行了测试,并对改性材料的结晶性能、流变性能和力学性能等进行了研究。结果表明,单环氧化合物能够在挤出过程中与PA6发生接枝反应,生成支化PA6产物;接枝链降低了PA6的结晶速率和结晶度,在宏观上相应地表现出材料力学性能的变化;GND最佳用量范围为1~3份,当其用量为1份时,相对于纯PA6,支化PA6的拉伸强度降低了8 %,断裂伸长率和缺口冲击强度分别提高了161 %和35 %。     

聚(苯乙烯-丙烯酰胺)/蒙脱土核壳结构材料改性聚酰胺6的性能研究

用自制的以有机蒙脱土（OMMT）为核、聚苯乙烯为次外层、聚丙烯酰胺为外层的新型聚(苯乙烯-丙烯酰胺)/OMMT核壳结构,通过熔融共混法制备了含3 %（质量分数,下同）核壳结构的改性聚酰胺6（PA6）。研究了改性PA6的力学性能、加工流动性能、结晶性能和热稳定性能。结果表明,核壳结构改性PA6能明显提高材料的弯曲性能,其弯曲强度较纯PA6提高了1.44 %,弯曲模量提高了3.46 %;核壳结构对PA6的结晶有成核作用,材料的结晶温度提高了8.5 oC,结晶度提高了3.3 %;核壳结构改性PA6与纯PA6具有基本一致的热稳定行为;核壳结构还能有效提高PA6的加工流动性,其熔体流动速率是纯PA6的2.18倍。     

SA／CaSt改陛氯氧化镁／MCA阻燃抗熔滴PA6的性能研究

以硫酸镁与氨水为原料,采用硬脂酸／硬脂酸钙作为复合改性剂,合成改性氢氧化镁阻燃剂。将制备的改性氢氧化镁与三聚氰胺氰尿酸盐（MCA）添加到尼龙（PA6）中,通过挤出造粒制备复合阻燃（PA6）。分别研究不同阻燃剂配比对复合材料力学性能、耐热性能、阻燃性能及机理的影响。结果表明：随着MCA／改性氢氧化镁比例的增大,复合阻燃PA6的拉伸性能与冲击性能均先上升后下降,当两者比例为1：1时,力学性能达到最优。同时,两阻燃剂协同作用,使尼龙6阻燃机理由解聚分解转化为直接炭化分解,有效抑制燃烧流滴现象,提高了复合材料的综合阻燃性能。     

硫酸钡填充改性聚酰胺66的研究

研究了聚酰胺66（PA66）／硫酸钡复合材料的形态结构和力学性能，探讨了硫酸钡的表面处理对复合材料形态结构的影响以及活化硫酸钡对复合材料力学性能的影响。结果表明，在20％（质量分数，下同）活化硫酸钡和5％的乙烯-辛烯共聚物熔融接枝马来酸酐共混改性PA66复合体系中，少部分的硫酸钡对PA66具有异相成核剂的作用，大部分的硫酸钡对PA66具有增韧作用。与未加活化硫酸钡的相比，材料的拉伸强度提高了11SPa、弯曲强度提高了12SPa，简支梁缺口冲击强度提高了9kJ／m^2。     

热引发官能化HDPE、PP、EPDM及其增韧PA66研究

采用热引发熔融接技方法研究了不同反应条件下马来酸酐（MAH）接枝HDPE、接枝共聚PP及接枝EPDM弹性体的接枝反应。结果表明：本热引发接枝法可避免接枝过程中的交联副反应，制得具有较高接枝率（接枝率在0.3%以上），较好熔体流动性能，较少凝胶含量的马来酸酐接枝HDPE、接枝共聚PP及接枝EPDM。采用机械共混法对已官能化的聚烯烃弹性体和聚烯烃塑料分别和混合增韧PA66的情况进行了比较，结果显示：采用PA66／改性聚烯烃弹性体／改性聚烯烃塑料三元共混体系，可以在较少用量的改性橡胶条件下使PA66的缺口冲击强度达到原材料的10倍以上，并且材料弯曲模量损失减少。SEM对PA66／EPDM－g-MHA/PP-g-MAH三元共混体系脆韧转变的研究结果表明：体系分散相中的EPDM－g-MAH向PA66基体扩散、渗透或形成嵌段共聚物的部分是增韧PA66中的有效成分。     

无卤膨胀阻燃PP/PA6合金性能研究

研究了以聚磷酸铵（APP）、三聚氰胺（MA）和层状复合金属氢氧化物（LDH）复配得到的膨胀阻燃剂（IFR）对聚丙烯／尼龙6（PP／PA6）合金性能的影响，分析了不同阻燃体系对PP／PA6合金的阻燃性能、力学性能、热性能和微观形态的影响。结果表明，当APP／MA／LDH为21．0／7．5／1．5（质量比）时，PP／PA6合金具有较好的阻燃性能并能保持较高的力学性能。LDH可以提高阻燃材料的热稳定性和残炭量，而且SEM照片显示炭层微观形态为“面包”状的膨松状。     

几种插层剂改性的MMT／PA66纳米材料的性能

用多种插层剂合成了有机改性蒙脱土（MMT），将PA66与改性MMT共混制成纳米材料，表征了其结构和力学性能。5％的纳米MMT1631能将PA66的冲击强度提高近50％，3％的MMT1827能将PA66的断裂伸长率提高52．5％，观察到MMT／PA66纳米塑料的无熔滴等阻燃特性，总结了不断插层剂改性MMT／PA66纳米材料的特点，发现MMT与常规阻燃剂之间有力学协效作用和阻燃协效作用，能提高PA66的力学性能和阻燃性能。     

11-氨基十一酸改性PA6的制备及性能研究

以己内酰胺、水、己二酸为原料,11-氨基十一酸作为改性剂聚合得到改性尼龙6(PA6),随后通过熔融纺丝成形后制备了改性PA6纤维,并对改性的PA6切片、纤维和织物进行了表征。结果表明:经11-氨基十一酸改性后,PA6切片中热水可萃取物的质量分数降低了3%,切片的饱和吸水率下降了大约5%,熔融温度从221.50℃下降到206.20℃,结晶温度从184.11℃下降到165.26℃,PA6纤维的模量和断裂伸长率下降,断裂强度有所提高;织物的硬挺度、弯曲刚度和弯曲滞后矩减小,说明改性后PA6织物的柔软性能变好,手感更活络。     

聚乳酸/尼龙11/氯醚弹性体三元共混体系结构与性能研究

以生物基尼龙11(PA11)和氯醚橡胶(ECO)作为聚乳酸(PLA)的增韧和耐热改性剂,通过熔融共混的方法制备了PLA/PA11/ECO三元共混体系,并系统表征了体系的相容性、形貌结构、热行为及物理性能.PA11的存在改善了共混体系组分之间相容性.连续相PA11能有效提高PLA基体的维卡软化温度至160 ℃以上.PLA...     

A comparison of the temperature dependence of the modulus, yield stress and ductility of nanocomposites based on high and low MW PA6 and PA66

Nanocomposites with both organically modified and unmodified silicate have been prepared by an extrusion process using low and high molecular weight grades of PA6 and a low MW grade of PA66. Mechanical properties have been tested at temperatures ranging from 20 to 120 °C. The modulus increase in all nanocomposites with organically modified nanocomposites is similar: at room temperature an increase in the modulus of approximately 10% for each wt% of silicate is found. PA66 nanocomposites display an identical normalized modulus increase as PA6 nanocomposites, while unmodified silicate nanocomposites show a smaller increase in the modulus. The yield stress also increases with the addition of layered silicate. Low MW PA6 and PA66 nanocomposites show brittle fracture behaviour at room temperature, while high MW PA6 nanocomposites are ductile. With increasing temperature all nanocomposites become ductile at a certain temperature.     

Dielectric property of modified barium titanate/polyamide 11 nanocomposites with different surfactants

Barium titanate/polyamide 11 (BT/PA11) nanocomposites were prepared by modifying BT nanoparticles with dry surface modification process, which had well dispersion, high dielectric constant, and low dielectric loss. Various methods were reported to improve dispersion and compatibility with complex process and high cost. Herein, three surfactants [ γ- aminopropyl triethoxy silane (KH550), sorbitan monostearate (SP60), and octadecyl phosphate ester (OPE)] were chosen to modify BT nanoparticles. Then modified-BT nanoparticles were blended with PA11. The structure was characterized by Fourier transform infrared, scanning electron microscope, and wide angle X-ray diffraction. Dielectric property was studied by broadband dielectric spectroscopy. The frequency dependence and temperature dependence of dielectric constant, dielectric loss, and dielectric modulus were analyzed. In general, dielectric property has strong frequency and temperature dependence. Furthermore, dielectric spectra shows that modified BT/PA11 nanocomposites have higher dielectric constant, lower dielectric loss, fewer interface polarization, and more dipole polarization. In contrast to three surfactants, OPE-BT nanoparticles have better effects, whose dielectric constant increases from 19 to 28 at 1 Hz, and dielectric loss decreases from 0.36 to 0.23. Meanwhile, mechanical property was characterized by universal testing machine. In all, the work improves dispersion of BT nanoparticles and dielectric property with easy process and low cost. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47447.     

(Nano)Fibrillar morphology development in biobased poly(butylene succinate-co-adipate)/poly(amide-11) blown films

Thin films with (nano)fibrillar morphologies were successfully obtained in fully-biobased poly(butylene succinate-co-adipate)/poly(amide-11) blends (PBSA/PA11, 85/15 wt/wt) using an extrusion-blowing process. Impacts of PA11 grade and take-up ratio on the morphology of PBSA/PA11 were particularly highlighted. Scanning electron microscopy analyses indicated that PA11 with high melt volume-flow rates are beneficial to the development of (nano)fibrillar morphologies in PBSA/PA11 blown film. On the contrary, unstable film blowing processing without fibrillar morphologies was attested for PA11 with low melt volume-flow rates. Increasing the take-up ratio during extrusion-blowing of PBSA/PA11 clearly generates finer PA11 (nano)fibrils into PBSA. Fibril diameters down to 300 nm could be reached with an optimal PA11 grade promoting enhanced mechanical properties (higher ductility and toughness). The formation of stable PA11 (nano)fibrils into PBSA is discussed via rheological assessments of viscosity/elasticity ratio. A specific attention was finally paid to the PBSA strain-hardening behavior in PBSA/PA11 using elongational rheological tests. PA11 (nano)fibrillation helps maintaining the strong PBSA strain-hardening and thus play a major role on the processability of PBSA/PA11 blends by extrusion blowing. As a conclusion, the PA11 grade represents a crucial parameter to control the production of PBSA/PA11 blown films with refined (nano)fibrillar structures and enhanced physico-chemical properties.     

二聚酸型聚酰胺热熔胶的应用与改性研究进展

介绍了二聚酸型聚酰胺(PA)热熔胶在制鞋、电子电器、汽车工业及热缩套管等行业中的应用情况,详细阐述了国内外学者围绕传统二聚酸型PA热熔胶耐低温性能差、粘接强度低等问题,在化学共聚、物理共混、成本降低及助剂等方面的改性研究进展。     

Inner surface modification of halloysite nanotubes and its influence on morphology and thermal properties of polystyrene/polyamide‐11 blends

The asymmetry of halloysite surface chemistry was used to perform a selective modification of its inner surface via grafting of a synthesized styrene/(methacryloyloxy)methyl phosphonic acid copolymer. Fourier transform infrared spectroscopy, thermogravimetric analysis (TGA) and pyrolysis gas chromatography/mass spectrometry were used to evidence and quantify the grafting. Then, raw and hybrid nanoparticles were incorporated in polystyrene (PS)/polyamide‐11 (PA11) blends (80/20 and 60/40 wt%). Scanning electron micrographs showed differences in localization of the halloysite nanotubes (HNTs), since raw halloysite is concentrated in the PA11 phase while modified halloysite is also located at the PS/PA11 interface, leading to a better interfacial adhesion between PS and PA11. An inhibiting effect of modified halloysite on PA11 coalescence was evidenced by measuring the particle size distribution of the extracted nodules. Moreover, the presence of modified halloysite at the interface shows an improvement in terms of thermal stability as observed by TGA, but with no significant effects on PA11 crystallization behaviour as shown by differential scanning calorimetry results. Rheological measurements were carried out to study the influence of the surface modification of halloysite on the blend morphology. A gel‐like behaviour was observed for the (60/40 wt%) HNTs reinforced composition that was enhanced in the case of 10% functionalized halloysite. © 2016 Society of Chemical Industry     

TiO2表面改性对聚酰胺6纤维强度及染色性能的影响

将TiO2表面包覆无定形TiO2,再经复配偶联剂改性后,分散在己内酰胺-水体系中乳化,于聚合釜中水解开环聚合,得到全消光聚酰胺6(PA6)切片。PA6切片经熔融纺丝制得PA6全消光纤维,并织成PA6全消光织物。用热重分析仪、纳米激光粒度仪、沉降试验等研究了改性TiO2的性能及在己内酰胺-水体系中的分散性;用差示扫描量热仪、扫描电子显微镜等研究了PA6全消光纤维结晶性能和截面形貌。结果表明：经复配偶联剂改性的TiO2在树脂基体中有很好的分散性;PA6全消光纤维的可纺性好;加入改性的TiO2后,PA6纤维的强度提高了25 %,但对PA6纤维的熔融温度没有影响;改性PA6全消光织物的上染率提高了10 %。     

聚醚砜-聚乙烯吡咯烷酮高温聚合物电解质膜及燃料电池堆性能研究

基于磷酸掺杂聚苯并咪唑膜（PA/PBI）的高温聚合物电解质膜燃料电池具有高的输出功率和优异的稳定性,然而PBI膜昂贵的价格和复杂的制备工艺限制了高温聚合物电解质膜燃料电池的商业化应用。本研究以成本低和制备工艺简单的聚醚砜-聚乙烯吡咯烷酮（PES-PVP）膜的商业化应用为目标,小规模制备了幅宽为40 cm的PES-PVP复合膜,证实了流延法放大制备PES-PVP复合膜的可行性。PES-PVP膜中每个PVP重复单元的吸附量达4.9个磷酸（PA）分子,且在180℃的质子电导率达85 mS·cm^-1。此外,尺寸为165 cm²的PA/PES-PVP高温膜电极在150℃的输出功率达0.19 W·cm^-2@0.6 V,与同尺寸的商业化PA/PBI高温膜电极的输出功率相当,并在近3000 h的寿命测试中展示出良好的稳定性。最后,将PA/PES-PVP高温膜电极（单片有效面积200 cm²）组装高温膜燃料电池短堆,其中基于3片膜电极的短堆展现出良好的电堆启停稳定性;基于20片膜电极电堆的峰值功率达1.15 kW。以上结果表明所制备的PA/PES-PVP是一种性能优良、价格便宜的高温聚合物电解质膜材料,并且基于该膜材料组装的高温聚合物电解质膜电池和电堆性能优异。本研究工作为高温聚合物电解质膜燃料电池关键材料和电堆的国产化提供了研究基础。     

Preparation of high-performance carbon nanotube/polyamide composite materials by elastic high-shear kneading and improvement of properties by induction heating treatment

Polyamide 66 (PA66) nanocomposites were prepared by compounding carbon nanotubes (CNTs) using an elastic high-shear kneading method, and the mechanism to understand their excellent properties was verified. In addition, we developed a microwave heat treatment that increases toughness quickly and at low cost. By combining 6.6 vol% or more of CNTs, PA66 with improved mechanical properties, such as higher elastic modulus and yield strength, was achieved, making it possible to obtain a composite having excellent high-temperature characteristics that does not melt even at a temperature above the melting point. These effects appeared to be due to defibration of CNT aggregates and isolation and dispersion in PA66. A lamellar crystal of PA66 grows around the CNT, forming an interphase. The higher performance appeared to be attributable to a continuous three-dimensional structure in which CNTs are bound via the interphase, and the improvement of the elastic modulus of the composite material was tentatively ascribed to a Halpin-Tsai model in which the size of the unit cell of the three-dimensional structure is introduced. The resulting CNT/PA66 composite materials are superior not only in performance but also in price.