长玻璃纤维增强PA66复合材料的综合性能及其影响因素研究

利用定制的熔融浸渍装置制备了长玻璃纤维增强聚酰胺66(PA66/LGF)复合材料,并对其力学性能、界面黏结性等进行了表征,探讨了玻璃纤维含量、润滑剂含量、相容剂含量以及切粒长度等因素对复合材料性能的影响,得到了PA66/LGF复合材料优化的配方设计与切粒长度.结果表明,当玻璃纤维含量为43％(质量分数,下同)、切粒长度...     

连续长玻纤增强PA6复合材料的制备与性能研究

通过熔压浸润工艺制备了连续长玻纤增强PA6复合材料,分别考察了PA6树脂流动速率、相容剂、粒子切粒保留长度对材料力学性能、浸润效果以及生产效率的影响。结果表明:提升树脂流动性可以提升玻纤的浸润效果,使用减链剂可以达到与合成的高流动树脂相当的流动特性,当减链剂含量超过1%时,冲击强度下降明显;相容剂种类对复合材料的力学性能影响较大,POE-g-MAH高温环境下热稳定性和活性不足,不适用于连续长玻纤增强PA6复合材料,POE-g-GMA可以大幅提高复合材料的力学性能;复合材料力学性能随粒子切粒保留长度的增加而增大,当粒子切粒保留长度超过12 mm时,力学性能开始下降,当粒子切粒保留长度超过15 mm时,性能劣化严重。确定当减链剂含量0.5%,POE-g-GMA添加量7%,粒子切粒保留长度10 mm时,各项性能达到最佳,与国外同类材料相比,具有显著的性能优势。     

间歇法PA66生产中黑粒产生的原因分析及对策

针对间歇法聚酰胺66树脂(PA66)生产中产品存在黑粒的问题，分析了生产工艺流程产生黑粒的原因，并提出相应对策。改造后，PA66树脂优等品率达95％以上。     

尼龙66与尼龙6及其共混物的熔融与结晶行为

分别将尼龙66(PA66)、尼龙6(PA6)以及不同比例的PA66/PA6共混物,经双螺杆挤出机挤出造粒,得到不同类型的PA粒料。使用自动黏度测定仪测试了挤出加工前后PA66和PA6的相对黏度,其中PA66和PA6的相对黏度分别下降了10.1%和2.5%。结果表明,PA66与PA6经过双螺杆挤出加工后都产生了降解现象,且在相同的加工条件下,PA66比PA6降解得更快。采用衰减全反射傅里叶变换红外光谱(ATR–FTIR)与差示扫描量热(DSC)法研究了PA66、PA6及其不同比例共混物的熔融与结晶行为。结果表明,加工历史对PA66与PA6的熔融与结晶行为影响很大,当两者共混时,PA6质量分数超过40%时共混物才开始出现PA6的熔融峰与结晶峰。     

玻璃纤维增强PA66复合材料作为高压开关设备绝缘件材料的可行性分析

选取不同短切玻璃纤维（SGF）含量的聚酰胺66（PA66）/SGF复合材料,研究对比PA66/SGF复合材料与热固性环氧树脂基绝缘材料的物理性能、力学性能和绝缘性能。结果表明,随着SGF含量的增加,PA66/SGF复合材料的密度增大,但均低于热固性环氧树脂基绝缘材料标准;弯曲强度、拉伸强度和冲击强度增大,当SGF含量达到20 %以上时,复合材料的综合力学性能达到热固性环氧树脂基绝缘材料标准;击穿强度和耐电弧时间增加,优于热固性环氧树脂基绝缘材料标准。因此,PA66/SGF复合材料作为高压开关设备绝缘件材料是可行的,但实际应用还需进一步的工程应用研究。     

高韧高强聚酮/聚酰胺66共混物的制备与性能研究

采用熔融共混法制备了聚酮（PK）/聚酰胺66（PA66）共混物,通过扫描电子显微镜、差示扫描量热仪、冲击试验机和电子万能试验机等研究了PK/PA66共混物的形态结构、结晶与力学性能。结果表明,当PA66含量较低时,PA66分散相粒径较小,且分布较均匀,PK/PA66（质量比为80/20）共混物的干态冲击强度达到29.5 kJ/m2,湿态下冲击强度为纯PK的4倍,同时共混物拉伸强度及弯曲模量也明显提高;但当PA66含量较高时,PA66相区尺寸明显增大,PK/PA66共混物的冲击强度呈下降的趋势;PA66的引入会显著降低PK的结晶度。     

PA66/TLCP共混物的结晶行为及力学性能研究

采用直接注塑法制备了聚酰胺66(PA66)/热致聚酰胺液晶(TLCP)复合材料,研究了共混物的结晶行为、晶体形貌和力学性能.DSC研究表明,PA66和TLCP有较好的相容性,随着TLCP含量的增加,PA66的结晶度、结晶速率下降.偏光显微照片显示,在PA66中加入TLCP后,PA66的球晶明显增大,晶界模糊,成为不规则的多面体.红外光谱分析表明,TLCP和PA66分子间存在着较强的相互作用,形成了大量的氢键.力学性能分析表明,当加入质量含量5%的TLCP时,PA66的拉伸强度、拉伸模量增幅最大,分别达25.4%、26.3%,当TLCP的质量含量小于5%时,PA66和TLCP分子间相容性较好,形成大量的分子间氢键,从而提高了力学性能;当TLCP的质量含量大于5%时,TLCP分子间形成了互锁的氢键,影响了共混材料力学性能的进一步提高.     

偶联剂对池窑法玻纤增强PA66性能的影响

用池窑法生产的高强短切玻璃纤维增强PA66，采用不同的偶联剂对玻璃纤维处理。通过试验验证及分析表明：玻纤增强PA66复合材料的拉伸强度、弯曲强度、硬度、简支梁冲击强度、热变形温度等性能比纯PA66都有不同程度的提高，玻纤质量分数在30％左右最佳；偶联剂A187在玻纤增强PA66中的辅助效果要优于偶联剂A1100。简单介绍了池窑法生产玻璃纤维的特点。     

尼龙66的环氧改性研究

采用环氧树脂(EP)对尼龙66(PA66)进行化学扩链改性,对改性PA66的力学性能、流变行为和耐热性能进行了测试和表征。结果表明,随着EP用量的增加,改性PA66的熔体体积流动速率(MVR)降低;当EP的质量分数为4.0%时,改性PA66的缺口冲击强度、拉伸强度、弯曲强度较纯PA66分别提高了50.2%、22.0%和44.7%。     

阻燃低气味增强尼龙的研究

制备了阻燃低气味的增强尼龙。分析了玻纤加入、尼龙类型和尼龙处理方式对尼龙力学性能的影响;并研究了阻燃剂种类和用量对玻纤增强尼龙性能的影响,最后研究了除味剂种类和用量对玻纤增强尼龙性能的影响。结果表明:短纤增强PA66具有较高的刚性和韧性;PA66经烘烤后所得玻纤增强PA66的刚性较高,而PA66不经烘烤所得玻纤增强PA66的韧性较高;红磷对玻纤增强的PA66阻燃效果好,且不对其力学性能产生影响;随着红磷阻燃母粒用量的增加,玻纤增强PA66的阻燃性能先变好后变差,在红磷用量为21份时达到最佳;凹凸棒石和红磷对玻纤增强PA66有优异的协同阻燃作用,当凹凸棒石用量为在4份时,达到最佳。SW-120和尼龙塑料除味剂同时使用,对玻纤增强PA66的气味有显著的改善。     

Morphology,thermal, and mechanical properties of polyamide 66/clay nanocomposites with epoxy‐modified organoclay

A new kind of organophilic clay, cotreated by methyl tallow bis‐2‐hydroxyethyl quaternary ammonium and epoxy resin into sodium montmorillonite (to form a strong interaction with polyamide 66 matrix), was prepared and used in preparing PA66/clay nanocomposites (PA66CN) via melt‐compounding method. Three different types of organic clays, CL30B–E00, CL30B–E12, and CL30B–E23, were used to study the effect of epoxy resin in PA66CN. The morphological, mechanical, and thermal properties have been studied using X‐ray diffraction, transmission electron microscopy (TEM), mechanical, and thermal analysis, respectively. TEM analysis of the nanocomposites shows that most of the silicate layers were exfoliated to individual layers and to some thin stacks containing a few layers. PA66CX–E00 and PA66CX–E12 had nearly exfoliated structures in agreement with the SAXS results, while PA66CX–E23 shows a coexistence of intercalated and exfoliated structures. The storage modulus of PA66 nanocomposites was higher than that of the neat PA66 in the whole range of tested temperature. On the other hand, the magnitude of the loss tangent peak in α‐ or β‐transition region decreased gradually with the increase in the clay loading. Multiple melting behavior in PA66 was also observed. Thermal stability more or less decreased with an increasing inorganic content. Young's modulus and tensile strength were enhanced by introducing organoclay. Among the three types of nanocomposites prepared, PA66CX–E12 showed the highest improvement in properties, while PA66CX–E23 showed properties inferior to that of PA66CX–E00 without epoxy resin. In conclusion, an optimum amount of epoxy resin is required to form the strong interaction with the amide group of PA66. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1711–1722, 2006     

碳纳米管-聚酰胺纤维改性邻甲酚醛环氧树脂

多壁碳纳米管(MWCNTs) 经酸化处理后与聚酰胺66（PA66)共纺制备MWCNTs-PA66纳米纤维膜后与邻甲酚醛环氧树脂（o-CFER）进行复合固化,制备了o-CFER/MWCNTs-PA66复合材料,并对其微观结构、力学性能和热性能进行了研究。结果表明,酸化MWCNTs表面引入了含氧基团,使PA66纤维膜的直径增大;o-CFER/MWCNTs-PA66复合材料的冲击强度、拉伸强度随MWCNTs含量的增加先增大后降低;当MWCNTs含量为0.5 %（质量分数,以PA66质量为基准）时,冲击强度和拉伸强度均达到最大值分别为0.29 kJ/m2和1.96 MPa,冲击强度较o-CFER树脂提高了23.2 %,较o-CFER/PA66复合材料提高了16.3 %,拉伸强度较纯o-CFER树脂提高了74 %;MWCNTs-PA66复合纤维膜能够提高o-CFER的耐热性。     

The effect of sample preparation on the mechanical properties of nylon 66

Cutting test specimens from molded plaques is commonly used in mechanical testing. The mechanical properties of these cut specimens may be affected by cutting process as it could introduce extrinsic flaws and thermal effects on cut edge surfaces. The objective of this experimental research is to determine how band saw cutting affects the flexural and impact strengths of 33% short glass fiber (GF) reinforced polyamide 66 (PA66) and unreinforced PA66. The specimens for the flexural and impact tests were obtained by cutting molded plaques using different blade types, blade speeds, feed rates, and levels of polishing. Results were compared with those from uncut specimens. Surface morphologies of the specimens' cut edges (photographs and roughness) were assessed using Scanning Electron Microscopy and PRK Perthometer, respectively. The results indicated that higher flexural and impact strengths of cut specimens of 33% GF reinforced PA66 were achieved with high blade speed, low work piece feed rate and using a high number of teeth per unit length. For unreinforced PA66, higher impact strengths were achieved at low blade speeds and work piece feed rates.     

PA66干切片在包装后储存时表面发黄现象分析及对策

改变干燥后的PA66树脂在包装时的温度及包装袋内的氧含量,并进行了分析试验.结果表明,包装时物料温度较高及包装袋内氧含量较高是导致干燥后的PA66树脂在储存时产生表面发黄现象的主要原因.依据此提出了解决办法及预防措施.     

玻璃纤维增强尼龙66改性研究进展

阐述了玻璃纤维增强尼龙66在增韧改性、阻燃改性、耐溶剂改性、耐磨改性、界面改性、复合改性和制备工艺改进等方面的研究进展。指出玻璃纤维增强尼龙66目前常用的增韧方法是与弹性体和高韧性聚烯烃共混,而阻燃改性的有效手段是添加微胶囊化红磷和P-N型阻燃剂。     

Morphological structure and mechanical properties of In situ microfibrillar composites of modified PA66 with PP

In situ microfibrillar composites (PP/mPA66) of modified polyamide66 (mPA66) with polypropylene (PP) were prepared by using a “post‐compatibilization” technique. The mPA66 was firstly obtained by reactive extrusion of PA66 resin with a specially designed compatibilizer, which was then blended with PP through extrusion combined with a hot stretching and subsequently quenching process. The PP/mPA66 in situ microfibrillar composites were comparatively studied with simply blended samples of PP/PA66 that were prepared by blending PA66 and PP together with (or without) the same compatibilizer through extrusion. PA66‐g‐PP (and/or elastomers) graft copolymer formation in mPA66 was identified by dissolution test and infrared spectroscopy measurement, the compatibilizer is unevenly dispersed with large domains in PA66 as observed by scanning electron microscope (SEM). In PP/mPA66 composites, the in situ generated PA66 microfibrils have a rather nonuniform diameter distribution and a very rough surface. SEM observations for the fractured surface illustrated that PP/mPA66 composites have structural characteristics of stronger adhesion and moderate flexibility of the interface. Enhanced compatibilization between the PA66 microfibrils with the PP matrix resulted in improved mechanical properties of the PP/mPA66 composites. With optimized composition, the PP/mPA66 composite has notched Izod impact strength, flexural modulus, and tensile yield stress of 1.49, 1.16, and 0.99 times as those of the neat PP, respectively. Such enhanced mechanical properties balance and improved interface adhesion were not found in the simply blended samples of PP/PA66 with or without the specially designed compatibilizer. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Thermal stability,flame retardance,and mechanical properties of polyamide 66 modified by a nitrogen–phosphorous reacting flame retardant

Flame‐retardant polyamide 66 (PA66) was prepared by the polymerization between PA66 prepolymer and N‐benzoic acid (ethyl‐N‐benzoic acid formamide) phosphamide (NENP). Compared with the pure PA66, the flame‐retardant PA66 exhibited better thermal stability, as indicated by thermogravimetric analysis results. The limiting oxygen index was 28% and the UL‐94 test results of the flame‐retardant PA66 indicated a V‐0 rating when the content of the NENP prepolymer was 5 wt %. The flammability and flame‐retardant mechanism of PA66 were also studied with cone calorimetry and scanning electron microscopy/energy‐dispersive X‐ray spectroscopy, respectively. The mechanical properties results show that the flame‐retardant PA66 resin had favorable mechanical properties. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43538.     

Polyamide 66/Clay Nanocomposites via Melt Intercalation

Polyamide 66/clay nanocomposites (PA66CN) were prepared via a melt compounding method using a new kind of organophilic clay, which was obtained through co‐intercalation of epoxy resin and quaternary ammonium into Na‐montmorillonite. The dispersion effect of silicate layers in the matrix was studied by means of XRD and TEM. The silicate layers were dispersed homogeneously and nearly exfoliated in the matrix as a result of the strong interaction between epoxy groups and PA66. The mechanical properties and heat distortion temperature (HDT) of PA66CN increased dramatically. The notched Izod impact strength of PA66CN was 50% higher than that of PA66 when the clay loading was 5 wt.‐%. Even at 10 wt.‐% clay content, the impact strength was still higher than that of PA66. The finely dispersed silicate layers and the strong interaction between silicate layers and the matrix reduced the water absorption, at 10 wt.‐% clay content; PA66CN only absorbs 60% water compared with PA66. The addition of silicate layers changed the crystal structure in PA66CN.     

Polymorphism in polyamide 66/clay nanocomposites

Polyamide 66/clay nanocomposites (PA66CN) were prepared via melt compounding method by using a new kind of organophilic clay, which was obtained through co-intercalation of epoxy resin and quaternary ammonium into Na-montmorillonite. The silicate layers were dispersed homogeneously and nearly exfoliated in polyamide 66 (PA66) matrix. The introduction of silicate layers induced the appearance of the γ phase in PA66CN at room temperature, more clay loadings would amplify this phenomenon; the addition of clay also changed the structure of the α crystalline phase. The presence of silicate layers increased the crystallization rate and had a strong hetero phase nucleation effect on PA66 matrix. The lower Brill transition temperature of PA66CN can be attributed to the strong interaction between polyamide chains and surfaces of silicate layers.     

PPE-g-MAH相容剂对增强PPE/PA66合金体系性能影响的研究

聚苯醚(PPE)与尼龙66(PA66)相容性较差,需要添加相容剂来提高PPE与PA66合金材料的界面相容性,研究了不同含量的相容剂对PPE/PA66合金性能的影响并确定了最佳配比.比较了不同含量的马来酸酐接枝聚苯醚(PPE-g-MAH)相容剂对PPE/PA66合金材料拉伸强度、弯曲强度、缺口冲击强度、非缺口冲击强度、热...