半芳香族耐高温聚酰胺（PA6T/10T/66）的制备及性能研究

二元共聚半芳香聚酰胺（PA6T/66）是一种低成本、高刚性、工艺较成熟的高分子材料，但韧性较差，具有一定的吸水率。文章在PA6T/66树脂中引入低吸水率脂肪族长碳链耐高温聚对苯二甲酰癸二胺（PA10T）链段，利用熔融聚合与微负压增黏相结合的方式制备PA6T/10T/66树脂。结果表明：制备PA6T/10T/66树脂时，PA10T盐最优加入量为5%。红外光谱表征PA6T/10T/66(45/5/50)树脂已完全聚合。差示扫描量热仪（DSC）测试PA6T/10T/66(45/5/50)树脂熔点为300℃。树脂黏度为2.5时，其拉伸强度达到50 MPa，弯曲强度为54 MPa。当聚合压力为2.35 MPa，封端剂用量占总盐质量为1.5%时，树脂黏度符合使用要求。此工艺成本低、制备过程简单，得到的三元共聚树脂适合玻纤改性、配色、注塑等应用。     

热氧老化对PA10T/GF复合材料性能及使用寿命的影响

用玻璃纤维(GF)对聚对苯二甲酰葵二胺(PA10T)进行改性得到PA10T/GF复合材料,通过控制熔融共混过程中GF的长度制备短GF增强PA10T(PA10T/SGF)复合材料和长GF增强PA10T(PA10T/LGF)复合材料。采用人工加速老化实验,研究热氧老化对PA10T/GF复合材料力学性能的影响,通过扫描电子显微镜(SEM)对PA10T/GF复合材料的冲击断面以及表面形貌进行分析,并预测了PA10T/GF复合材料的使用寿命。结果表明,PA10T/LGF复合材料的拉伸、弯曲强度以及缺口冲击强度较PA10T/SGF复合材料的高;在240℃下热氧老化50 d后,与PA10T/LGF复合材料相比,PA10T/SGF复合材料具有更好的耐老化性能;SEM分析表明,PA10T/GF复合材料的热氧老化机理主要是由于PA10T树脂的降解所引起的PA10T与GF界面作用的削弱;而通过寿命预测发现当使用温度为150℃时,PA10T/LGF和PA10T/SGF复合材料的使用寿命分别为101 d和86 d,在温度低于172℃时,PA10T/LGF复合材料比PA10T/SGF复合材料具有更长的使用寿命。     

玻璃纤维增强生物基PA10T复合材料的制备及性能研究

由癸二胺和对苯二甲酸缩聚而成的新型生物基半芳香族聚酰胺材料——聚对苯二甲酰癸二胺(PA10T),其生物基质量分数为40%～60%,碳排放优势明显，可以满足可持续发展需要。以PA10T作为基体树脂，玻璃纤维(GF)作为增强材料，通过熔融挤出法制备了一系列GF增强PA10T复合材料，并对材料的力学性能进行了研究。结果表明：随着GF增强体含量的逐渐增加，所制备的GF增强PA10T复合材料的拉伸强度、弯曲模量和缺口冲击强度均逐渐增加。当GF增强体的添加质量分数为35%时，所制备的PA10T复合材料(PA10T-GF35)的拉伸强度为194.8 MPa,弯曲模量为10 246.8 MPa,缺口冲击强度为8.8 kJ/m²。此外，对PA10T-GF35复合材料的非等温结晶性能、耐冷冻液性能和加工性能进行了相关研究，结果表明：相较于聚酰胺66(PA66)和聚对苯二甲酰己二胺/聚酰胺66共聚物(PA6T/66),PA10T作为基体树脂所制备的PA10T-GF35复合材料展现出更好的耐冷冻液性能；同时，添加CYD-819可以明显改善PA10T复合材料的加工流动性能。     

高温尼龙研究进展

回顾了高温尼龙(PA)的发展历程,介绍了PA10T、PA4T、PXD10、PA12T、PA5T和PA6C等新型高温PA的性能特点及主要生产厂商,并指出高温PA的发展趋势。     

半芳香族耐高温尼龙PA6T/10T的合成及应用

利用癸二胺,己二胺和对苯二甲酸为聚合单体,以去离子水为溶剂,通过预聚合/固相增黏的工艺合成了半芳香族耐高温尼龙聚对苯二甲酰己/癸二胺(PA6T/10T)。采用傅里叶变换红外光谱、核磁共振碳谱对合成的PA6T/10T树脂进行了结构表征,并研究了PA6T/10T和聚(对苯二甲酰/己二酰)己二胺(PA6T/66)的熔点和结晶温度以及玻璃纤维(GF)增强改性PA6T/10T和PA6T/66的热失重行为、力学性能及耐热氧老化性能。结果表明,与传统的PA6T/66相比,合成的PA6T/10T结晶温度提升5℃,结晶半峰宽缩短了10.6℃,结晶速率明显提升;与GF增强PA6T/66相比,GF增强PA6T/10T的力学性能无显著差异,其初始分解温度提高16℃,热稳定性明显改善;GF增强PA6T/10T与GF增强PA6T/66的初始反射率及亨特白度相近,但经180℃热氧老化3h和表面贴装无铅回流焊接机过炉老化3次后,前者的反射率和白度均明显高于后者,表明GF增强PA6T/10T具有更好的耐热氧老化性能和耐黄变性能。     

增韧剂和偶联剂下GF增强PA复合材料性能表征分析

选择双螺杆挤出机来制备以尼龙(PA)6T/66与PA10T为基础的玻璃纤维(GF)增强复合材料,分析马来酸酐接枝聚烯烃弹性体(POE-g-MAH)增韧剂对PA复合材料的力学特性改变作用。研究结果表明:将POE-g-MAH加入含20%GF的PA66复合材料基体后,试样的弯曲、拉伸强度以及弯曲弹性模量都发生了减小;对于含GF为20%的PA10T,弯曲弹性模量逐渐减小,拉伸与弯曲强度则先增大后减小。在加入了5%POE-g-MAH的复合材料断面中,出现了较多数量的褶皱,POE-g-MAH能够使GF和PA6T/66之间形成更良好的界面结合性能,显著提高界面相容性。加入偶联剂会导致PA6T/66体系力学性能的明显改善。加入POE-g-MAH可以改善树脂的界面相容性能,提高GF和树脂的结合强度。     

透明尼龙PA6T/6I在GF增强PA66体系中的应用

采用尼龙66 (PA66)和透明尼龙PA6T/6I为基体树脂,用熔融共混改性的技术方法制备PA66/PA6T/6I/GF复合材料,考察了透明尼龙PA6T/6I含量对复合材料的熔融结晶行为、热变形温度(HDT)、力学性能、表面性能的影响。结果表明,当玻璃纤维含量为30%的情况下,在透明尼龙树脂PA6T/6I用量不高于基体树脂含量的20%时,改性复合材料熔融结晶行为与PA66类似,复合材料制品表面的浮纤问题得到解决,比未添加透明尼龙PA6T/6I的复合材料相等的拉伸强度和弯曲强度分别提高27%和40%,简支梁和悬臂梁缺口冲击强度则分别提高了26%和40%,吸水率提高了30%,具有优异的综合性能和尺寸稳定性。     

高性能碳纤维增强尼龙10T复合材料制备与性能

以半芳香族尼龙聚对苯二甲酰葵二胺(PA10T)为基体树脂,采用碳纤维(CF)增强改性的方式制备高性能CF增强PA10T复合材料,研究不同质量分数的CF对PA10T/CF复合材料力学性能的影响。通过扫描电子显微镜对PA10T/CF复合材料的断面形貌进行分析,结合X射线衍射分析和差式扫描量热分析对复合材料的熔融、结晶过程和晶体结构进行分析,采用热重分析测试了复合材料的热稳定性。结果表明,CF的加入显著提高了PA10T/CF复合材料力学性能,当CF质量分数为30%,PA10T/CF复合材料的拉伸强度、弯曲强度和弯曲弹性模量分别达到253,360 MPa和20.1 GPa,比纯PA10T的性能分别提高216%,323%和675%。CF在复合材料结晶过程中起到异相成核作用,为结晶过程提供大量晶核,CF诱导α晶型PA10T晶态结构发生变化;同时也对分子链的运动折叠产生阻碍,导致晶粒生长不完善出现晶粒细化现象。加入CF后,复合材料结晶温度提高,结晶度随CF含量提高呈先下降后上升的变化趋势,同时热稳定性提高,当CF质量分数为10%时,复合材料热分解起始温度及失重50%的温度分别比纯PA10T提高10....     

耐高温聚酰胺的性能及应用

列举了几种主要耐高温聚酰胺(PA)的结构,介绍了耐高温PA的主要性能,如耐热性、加工性、吸水性、结晶性、回流焊性及化学性能。详细叙述了主要耐高温PA如PA46、PA6T、PA9T、PA10T的各种性能优势及主要应用。最后,指出耐高温PA在汽车工业、电子电气工业领域具有很好的应用前景。     

耐高温尼龙的发展与应用

介绍了国内外目前耐高温尼龙(PA)的主要制备工艺,包括高温高压溶液缩聚法、低温溶液缩聚法、胺酯交换法、界面聚合法和直接熔融缩聚法;耐高温尼龙产品种类主要包括聚酰胺(PA)46,PA4T,PA6T,PA9T,PA10等;耐高温尼龙的下游主要应用领域包括电子电器、汽车制造、LED等领域.重点分析了不同合成工艺的研究进展以及...     

蜡梅花头香的富集及其化学成分研究

用顶空和不同吸附剂吸附法收集蜡梅花的头香,并用GC-MS法对其进行了化学成分研究。对比了不同吸附剂在相同条件下对蜡梅花头香的吸附量与吸附成分。结果表明,不同吸附剂吸附的头香量和化学成分不同。大孔树脂的吸附量是0.22 g,且不具有蜡梅花香味,是自身分解物;阳离子交换树脂、凹凸棒石、活性炭、分子筛吸附量分别是0.52、0.42、0.26、0.29 g,检测出的化学成分种类分别是27、24、12、10种,且与蜡梅花的香味相似;后4种吸附剂所吸附的头香总成分约39种。凹凸棒石和阳离子交换树脂是蜡梅花头香成分的适宜吸附剂。     

Influence of thermo‐oxidative aging on the dynamical mechanical properties and thermal degradation kinetics of glass fiber‐reinforced PA10T composites

Unveiling the fundamental thermal‐oxidative aging mechanism and thermal degradation kinetics of the poly(decamethyleneterephthalamide) (PA10T)/ glass fiber (GF) composites under different aging temperatures (160°C, 200°C, and 240°C) for 0–50 days will facilitate the understanding of the interaction between matrix PA10T and GF. The results revealed that the decrease of mechanical properties referring to tensile strength, flexural strength and notched impact strength, and the occurrence of debonding phenomenon between PA10T matrix and GF were increasingly obvious after longer aging time at higher aging temperature. At the same time, the decline of crystalline was mainly ascribed to the thermal‐oxidative aging effect, which triggered the deterioration of mechanical properties of PA10T/GF composites. Accordingly, the enhancement of rigidity were probably attributed to the higher temperature aging effect with the aging time prolonging in PA10T/GF composites, while the interfacial debonding between GF and resin matrix obviously occurred with the increase of aging time. In a word, it is believed that investigating the fundamental thermal‐oxidative aging of PA10T/GF composites would be beneficial to optimize and control the service life and applications of materials. POLYM. ENG. SCI., 59:643–656, 2019. © 2018 Society of Plastics Engineers     

阻燃型玻纤增强PA10T复合材料的热氧老化性能

采用溴化环氧树脂对聚对苯二甲酰葵二胺(PA10T)进行改性,并通过熔融共混法制备阻燃型玻璃纤维(GF)增强PA10T复合材料,采用人工加速热氧老化手段,研究了热氧老化对其力学性能的影响,并用扫描电子显微镜(SEM)对复合材料的冲击断面形貌进行观察。结果表明,随热氧老化时间增加,复合材料的拉伸强度、弯曲强度和缺口冲击强度均下降明显,分子链松弛过程减弱;老化10 d后,复合材料的弯曲弹性模量仅略有下降而储能模量达到最大值,表明在热氧老化初期PA10T分子链之间发生了微交联,但随老化时间继续增加,两者均下降明显。SEM结果表明GF与树脂基体之间界面粘接作用的强弱是影响材料热氧老化性能变化的主要因素。     

合成树脂乳液涂料中挥发性有机化合物含量测定

建立了气相色谱质谱联用法测定合成树脂乳液涂料中挥发性有机化合物含量的方法。合成树脂乳液涂料经甲醇提取、离心,上清液用HP-5MS色谱柱分离,质谱检测,内标法定量。优化条件下挥发性有机化合物回收率为85.84%~103.47%,相对标准偏差(RSD)为0.49%~1.86%,检出限为6.5~12.5mg·L-1。该方法操作简单,准确度和精密度较高,是一种检测合成树脂乳液涂料中挥发性有机化合物含量的有效方法。     

基于PLSR分析云烟浸膏挥发性成分对卷烟感官品质的影响

采用大孔树脂分离纯化法、超临界CO2萃取法、分子蒸馏法对云烟浸膏进行改良处理,制备烟草精制物,对精制物进行挥发性成分分析和感官评吸,采用偏最小二乘回归法(PLSR)对云烟浸膏中挥发性成分与卷烟感官品质进行相关性分析发现:挥发性成分对口腔刺激/舌部灼烧、烟气浓度、劲头这三个指标影响建立的模型拟合度最高,能够有效解释挥发性...     

Meeting the challenge of formulating for the future

The history of the paint market shows that change quickly follows new technical advances or governmental regulation. Restrictions on the use of volatile organic compounds (VOCs) in architectural coatings are no exception. This paper examines the history of VOC regulations and resin technology in Europe compared to the U.S. Despite differences in formulations, substrates, and test methods, there are lessons that can be applied by U.S. paint makers and their suppliers. Other new directions in polymer synthesis and technology which may impact the paint industry are also discussed. Presented at the 78th FSCT Annual Meeting, November 5, 2001, in Atlanta, GA 7201 Hamilton Blvd., Allentown PA.     

特种共混型热塑性弹性体——Ⅱ.CPE及CSM与PA共混体系的组成对性能的影响

以CPE、CSM 及PA为原料,采用动态硫化法制备了具有特殊性能的共混型热塑性弹性体,考察了各种因素对共混物性能的影响,比较了 CPE/PA 和 CSM/PA 的综合性能。结果表明,橡胶相的交联程度对共混物的综合性能有较大影响;在 CPE/PA 共混体系中,DCP 交联体系较促进剂 NA-22 为优;助交联剂 TAIC 在本体系中起改性作用;白炭黑在共混体系中无明显补强效果,但经表面处理后,可提高橡胶相的交联程度;从共混物的返炼特性判断,当 CPE/PA(质量份)为 90/10—80/20时发生相转变;CPE/PA 的综合性能较 CSM/PA 为优。     

Control of microvoids in resol phenolic resin using unsaturated polyester

A major drawback of cured phenol formaldehyde resin is the presence of microvoids, resulting from the liberation of condensation byproducts. In an attempt to rectify this, phenolic resol resin was blended with unsaturated polyester (UP). UPs with various maleic anhydride (MA) to phthalic anhydride (PA) ratios were synthesized and later mixed with resol resin in various proportions. The best MA/PA ratio was found out by determining the specific gravity, acetone‐soluble matter, and volatile content of the cast blend, cured under a satisfactory time–temperature schedule. The influence of acid value of the UP and the most desirable UP content were also investigated on the basis of the quality of the modified phenolic samples. The structural changes in the modified resin were studied using FTIR spectroscopy. Scanning electron micrographs (SEM) of the fractured surfaces were obtained to ascertain the extent of microvoids in the modified resin. Both thermogravimetric analysis results and SEM micrographs confirm the effectiveness of UP in reducing the microvoids in the cast resol resin. The tensile and impact strengths of the samples also reflect the superior quality of the resol phenolic resins that have been modified by UP. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Microstructure and crystallography in microcellular injection‐molded polyamide‐6 nanocomposite and neat resin

The effects of adding nanoclay to polyamide‐6 (PA‐6) neat resin, and the effects of processing parameters on cell density and size in microcellular injection‐molded components were investigated. In addition, the crystal sizes, structures, and orientation were analyzed with the use of x‐ray diffraction (XRD) and a polarized optical microscope. The standard ASTM D 638‐02 tensile bars for the analyses were molded according to a fractional four‐factor, three‐level, L9 Taguchi design of experiment (DOE) with varying melt temperature, injection speed, supercritical fluid (SCF) concentration, and shot size. It was found that the presence of montmorillonite (MMT) nanoclay greatly reduced the size of the cells and crystals, but increased their density in comparison with neat resin processed under identical molding conditions. In addition, at the sprue section downstream of the machine nozzle, cell size gradually decreased from the part center toward the skin for both the neat resin and the nanocomposite. It was also found that shot size was the most important processing parameter for both the neat resin and nanocomposite in affecting cell density and size in microcellular injection molding components. Weakly preferred crystal orientations were observed on the surface of microcellular injection‐molded PA‐6/MMT tensile bars. Finally, the addition of nanoclay in PA‐6 neat resin facilitated the formation of γ‐phase crystals in the molded components. Polym. Eng. Sci. 45:52–61, 2005. © 2004 Society of Plastics Engineers.     

全叶青兰挥发性成分

采用顶空固相微萃取结合色谱质谱技术分析了全叶青兰中挥发性成分的组成和含量。结果表明,6 min和30 min的顶空吸附时间所测得的全叶青兰中挥发性成分的组分基本一致,但各组分所占的比例有一定差异。全叶青兰挥发性成分中以萜烯类为主的碳氢化合物约占其总质量的50%,醇类化合物约占20%,其他成分的质量分数高低依次为酯、酮、萜烯氧化物和醛类化合物,醚、胺及含硫化合物等质量分数极低。