PE-HD/棉秆皮复合材料的制备及其性能研究

采用蒸汽爆破对含水率分别为30 %、40 %、50 %的棉秆皮进行预处理,并与高密度聚乙烯（PE-HD）复合制备PE-HD/棉秆皮复合材料,研究了蒸汽爆破、棉秆皮含量、棉秆皮含水率对PE-HD/棉秆皮复合材料力学性能和密度的影响。结果表明,与未经蒸汽爆破处理的PE-HD/棉秆皮复合材料相比,蒸汽爆破预处理后制备的PE-HD/棉秆皮复合材料的力学性能更好;当棉秆皮含量为30 %时,复合材料的综合力学性能最佳;复合材料的拉伸强度随棉秆皮含水率的增加而提高;复合材料的弯曲强度在棉秆皮含水率为40 %时达到最大值。     

棉皮纤维增强聚丁二酸丁二醇酯复合材料的热性能及力学性能研究

采用连续式蒸汽爆破法对棉皮纤维进行预处理,将其与聚丁二酸丁二醇酯(PBS)进行共混,制备了PBS/棉皮纤维复合材料。利用扫描电镜对棉皮纤维及PBS/棉皮纤维复合材料的微观形貌进行了分析,并研究了棉皮纤维含量对PBS/棉皮纤维复合材料熔融及结晶行为、热降解性能、热变形温度以及力学性能的影响。结果表明:经蒸汽爆破处理后,棉皮纤维直径变小,比表面积变大,在PBS基体中分散均匀;棉皮纤维的存在改变了PBS的熔融峰值温度,提高了其结晶度;与纯PBS相比,PBS/棉皮纤维复合材料在高温条件下的热稳定性得到改善维,卡软化温度和弯曲强度提高。     

棉皮纤维增强LDPE复合材料的拉伸性能

采用蒸汽爆破装王对棉皮进行预处理,在高温高压水蒸汽的条件下改变棉皮内部结构,并制备LDPE/棉皮纤维复合材料标准拉伸样条.从外观形态、扫描电镜方面对蒸汽爆破改性后棉皮纤维进行分析,并研究了蒸汽爆破压力对LDPE/棉皮纤维复合材料拉伸性能的影响,结果表明:蒸汽爆破预处理方法能有效解决界面粘结问题,提高LDPE/棉皮纤维复合材料的拉伸性能,当压力为1.6 MPa时,所获得的拉伸强度最佳.     

连续式蒸汽爆破对PP/棉杆纤维复合材料力学性能的影响

以连续式蒸汽爆破预处理的棉杆作为增强纤维,通过模压成型制得聚丙烯(PP)/棉杆纤维复合材料.研究了蒸汽爆破条件中纤维含水量及爆破次数对复合材料力学性能的影响.结果表明,该预处理使复合材料力学性得以改善.当纤维含水量为40%、爆破次数两次时,获得的复合材料综合力学性能最佳.     

PBS/蔗渣复合材料的制备与性能

用蒸汽爆破后的甘蔗渣纤维(BF)与聚丁二酸丁二醇酯(PBS)制备复合材料,研究温度以及蒸汽爆破预处理对复合材料力学性能的影响,并通过红外光谱和电子扫描电镜分析其作用机理.结果表明:随着温度的升高,纤维的分散性、BF与PBS的界面粘结性能及复合材料力学性能提高,温度为200℃时复合材料的拉伸性能最佳,在温度为230℃时弯曲性能和冲击性能达到最佳;而蒸汽爆破预处理可提高纤维素的含量,增大纤维比表面积,使复合材料的力学性能得到改善.     

蒸气爆破预处理棉皮纤维对复合材料力学性能的影响

采用自行设计的蒸气爆破装置对棉秆皮进行预处理并对处理后纤维的外观形态等方面进行了研究;使用正交试验设计来研究蒸气爆破预处理的爆破压力、含水率、保压时间等参数以及纤维的含量对线型低密度聚乙烯(LDPE)棉/皮纤维复合材料力学性能的影响程度和显著性。结果表明:植物纤维的含量对复合材料的拉伸强度和弯曲强度性能影响呈高度显著,爆破压力对复合材料的拉伸强度和弯曲强度性能影响呈显著,含水率对拉伸强度有影响,但对弯曲强度影响不显著,而保压时间对两个试验指标的影响都不显著。     

蒸汽爆破预处理对LDPE／棉皮纤维复合材料力学性能的影响

采用蒸汽爆破预处理过的棉皮作为增强纤维,通过模压成型制备LDPE/棉皮纤维复合材料,研究了爆破压力、棉皮纤维质量分数对LDPE/棉皮纤维复合材料力学性能的影响.实验结果表明,该复合材料的力学性能得到了改善,当压力为1.8 MPa、棉皮纤维质量分数为35%时,所获得的拉伸强度和弯曲强度为最佳.     

乙酸酐处理棉秆皮纤维增强聚丙烯复合材料的制备及性能研究

以棉秆皮纤维为增强相、聚丙烯为基体相,制备4 mm厚、棉杆皮纤维含量为 30 %（质量分数,下同）的聚丙烯/棉秆皮纤维复合材料薄片,棉秆皮纤维先经NaOH预处理,再经过乙酸酐（浴比30∶1、浸泡30 min、温度30 ℃）改性处理后,复合材料的拉伸断裂强度和弯曲断裂强度都达到最高,相比未改性的分别增大了6.33 %和11.72 %。     

PBS/剑麻复合材料制备与性能研究

利用蒸汽爆破预处理剑麻纤维(SESF)作为增强体,通过模压成型制备聚丁二酸丁二醇酯(PBS)/SESF复合材料,研究了SESF质量分数对复合材料力学性能的影响。对比了在剑麻纤维质量分数为30%的条件下,和未经预处理的2种剑麻纤维制得的复合材料的力学性能,并通过扫描电镜(SEM)对试样进行观察分析。结果表明,随着SESF质量分数的增加,复合材料的拉伸强度先增大后减小,在SESF质量分数为30%时达到最大值,比纯PBS的提高了15.5%;弯曲强度和弯曲模量均随剑麻纤维质量分数的增大而提高,其中弯曲强度在SESF质量分数为30%时的比纯PBS的提高了132.5%;断裂伸长率和冲击强度随着SESF质量分数的增加而降低。     

柔韧棉秆皮纤维/PLA复合材料的制备与性能

采用抄造与热压相结合的方法,制备了薄且柔韧的棉秆皮纤维/聚乳酸(PLA)复合材料。该复合材料是由聚乳酸包覆、填充的棉秆皮纤维网,具有较好的柔韧性。研究了棉秆皮纤维与聚乳酸质量比和热压时间对复合材料结构、拉伸性能和弯曲刚度的影响。结果表明,棉秆皮纤维与PLA质量比为1/1,热压15 min(温度190℃)为最佳条件。该条件制得的复合材料厚(0. 126±0. 006) mm,干、湿态下的拉伸强度分别为12. 15、4. 88 MPa,断裂伸长率分别为1. 55%、1. 5%,杨氏模量分别为1 126、508 MPa,弯曲刚度为0. 35 N·cm2/cm。该研究为纤维增强热塑性复合材料的制备方法提供了新的思路,也有利于提高废弃棉秆皮的利用率。     

国外复合材料用高级增强纤维的发展现状

本文综述了国外碳纤维、陶瓷、聚芳酰胺、超高分子量聚乙烯、液晶聚合物纤维的发展现状,包括它们的生产能力、消费情况、性能特点,主要生产国和生产公司、产品牌号以及应用领域等,并指出了其生产进展和发展动向。     

剑麻纤维与玻纤混杂增强PVC复合材料的性能研究

本文介绍采用短麻纤维(SF)和短玻纤(GF)混杂增强PVC基体,测定了复合材料的弯曲强度、弯曲模量、无缺口冲击强度以及耐水浸泡性能,并探讨了这一复合材料在水浸泡前后的力学性能及其界面行为.结果表明,此种复合材料在弯曲模量和无缺口冲击强度上存在正的混杂效应,而弯曲强度存在负的混杂效应;经水浸泡后,复合材料的弯曲强度、弯曲摸量和冲击强度都有不同程度的下降,而对于纯PVC基体,水浸泡后的弯曲强度和弯曲模量反而有所提高,因此可以认为,水浸泡对纯PVC基体在弯曲性能方面无不良影响,水分主要对纤维与基体的界面产生不良作用,导致复合材料性能下降.     

纤维填充PTFE复合材料的摩擦学研究

在聚四氟乙烯（PTFE）中分别填充碳纤维（CF）、玻璃纤维（GF）及这两种纤维不同配比的混杂纤维（HF），制备了具有不同力学性能和摩擦磨损性能的PTFE基复合材料。探讨了填料组成对复合材料硬度和干摩擦条件下摩擦磨损性能的影响，并研究了PTFE基复合材料磨损表面的形貌学。结果表明，适量填充CF和GF均可提高PTFE的摩擦磨损性能，CF比GF效果更为显著；CF和GF的混杂纤维填充PTFE复合材料．表现出一定的协同性，比填充单种纤维，其效果更显著。     

缠绕玻璃钢管道轴向强度设计

本文分析了输液管道不同工作及安装条件下的受力状态,提出缠绕玻璃钢管道轴向强度设计准则问题,建议合理设计缠钲 管道的缠绕角,以利于降低工程造价,促进玻璃钢管道的广泛应用。     

莫代尔纤维的性能与应用

将莫代尔和普通粘胶纤维的主要性能进行了比较，突出了莫代尔纤维的独特性，并概括了莫代尔纤维应用和前景。     

麻纤维/玻璃纤维混杂增强聚丙烯复合材料的性能研究

采用新的混杂复合工艺,将不同形式的玻璃纤维、剑麻纤维、玻璃纤维毡与黄麻纤维毡用不同的混杂方式（Ⅰ层内,Ⅱ夹芯）混杂增强聚丙烯.研究结果表明,在强度和刚性得到明显改善的同时,冲击韧性得到了大幅度的提升,而且短纤维层内混杂和连续纤维夹芯混杂呈现出不同的特点,不同的铺层设计导致力学性能有明显差异.通过对材料断面的电镜分析看出,用短玻璃纤维和麻纤维毡混杂增强聚丙烯时,冲击破坏过程以界面脱黏为主,而用玻璃纤维毡和麻纤维毡混杂增强时,破坏断面中玻璃纤维存在大量的拔出现象.利用混杂效应理论公式计算了混杂效应系数,并和实测值进行了比较.     

Quality Changes of Superheated Steam–Dried Fibers from Oil Palm Empty Fruit Bunches

Conventional drying of the fibers from oil palm empty fruit bunches (EFB) using flue gas from diesel burners frequently causes browning and dust explosion. Replacing the drying medium with superheated steam is expected to improve the quality of EFB fibers as well as improve the safety of the dryer operation. In this study, the effects of steam temperature and steam velocity on the quality of steam–dried EFB fibers was investigated. The drying experiment was carried out at atmospheric pressure with steam superficial velocity in the range of 0.3 to 0.49 m s^?1 and temperature in the range of 135 to 200°C. Three quality parameters of the EFB fibers, the color, strength, and microstructure, were used to assess the changes in EFB fiber quality as a result of superheated steam drying. The color of the EFB fiber was either improved or not significantly degraded. The strength of the superheated steam–dried EFB fibers was higher than that of undried and hot air–dried EFB fibers. The microstructure of fresh undried EFB fibers as seen by scanning electron microscopy (SEM) showed the presence of round silica particles of 10–20 µm in diameter all over the EFB fiber strand, which complicates pulping and bleaching. Superheated steam drying successfully removed the silica particles from the EFB fibers at temperatures of at least 200°C and a velocity of steam of at most 0.49 m s^?1, which is better than hammering, which can only remove 88% of the silica particles. The high temperature of the superheated steam loosened the silica particles from their craters. The EFB fibers cracked and split at steam velocities at or above 0.49 m s^?1 and high superheated steam temperatures at or above 200°C and as a consequence became weaker at these conditions. The removal of silica particles by superheated steam drying makes the EFB fiber amenable to pulping and bleaching. Superheated steam drying is therefore found to improve the overall quality of EFB fibers compared to hot air drying.     

聚合物光纤

本文介绍了聚合物光纤的特性及其分类,论述了9种聚合物光纤的性能及其应用,综述了当今聚合物光纤的发展和现状。     

Description and modeling of fiber orientation in injection molding of fiber reinforced thermoplastics

As mechanical properties of short fiber reinforced thermoplastic injected components depend on flow induced fiber orientation, there is considerable interest in validating and improving models which link the flow field and fiber orientations to mechanical properties. The present paper concerns firstly the observation and quantification of fiber orientation in a rectangular plaque with adjustable thickness and molded with 30 and 50 wt% short fiber reinforced polyarylamide. An automated 2D optical technique has been used to determine fiber orientations. A classical skin (with orientation parallel to the flow)-core (with orientation perpendicular) structure is observed for thick plaques (thickness greater than 3 mm) but the core region is fragmentary for thickness less than 1.7 mm. It is shown that the gate design and different levels of fiber interactions, due to different fiber concentrations, are responsible for these observations. Secondly, computer simulations of flow and fiber orientation are shown. The agreement with the actual data is good, except in the case of the core for thin plaques. The limitations that have to be resolved come not only from the standard fiber orientation equations, but also from the flow kinematics computation.     

Thermostatic pyrolysis process of cured polycarbosilane fiber

As precursor fiber of advanced SiC fiber, cured polycarbosilane (PCS) fiber is prepared, and thermostatic pyrolysis of this fiber is studied in detail. Since the weight change is the most important characteristic of the pyrolysis degree of cured PCS fiber, a precise balance is applied on-line to follow the weight change of the cured PCS fiber, which was carried out in a standing style furnace. In thermostatic pyrolysis, the degree of pyrolysis, which is characterized by the weight loss of the fiber, and the properties of the final SiC fibers were found to be strongly dependent on the process conditions such as N² flow and the amount of fibers. From much evidence, it is the offgas evacuated in the process that plays an important role by accelerating pyrolysis and increasing pyrolysis degree.