基于废弃混纺纤维循环利用的板材成型技术及其性能

针对涤/棉、棉/麻混纺纤维材料废弃量多及难以再利用的问题,使用共混塑炼法制备以废弃聚丙烯颗粒为基体材料,废弃涤/棉/麻混合纤维为增强材料的复合板材,设计并优化了成型工艺,测定了板材的冲击和拉伸强度。通过单因素和正交试验得出了复合板材的优化生产工艺条件,并分析了复合板材成型工艺参数与其冲击和拉伸强度之间的关系。     

废弃纤维/热塑性聚氨酯保温阻燃复合材料的制备及性能

为了开发废弃纤维循环利用新途径,以废弃纤维为增强材料,废弃热塑性聚氨酯(TPU)为基体材料,通过共混-塑炼机压法制备保温阻燃复合材料。以热传导系数、拉伸强度等为检测指标,通过极差和方差分析优化出最优工艺参数:废弃纤维含量15%,发泡剂偶氮二甲酰胺(AC)含量2%,阻燃剂聚磷酸铵(APP)含量20%,膨胀蛭石(EVMT)含量3%,热压温度175℃,热压压力1 MPa,硅烷偶联剂(KH550)含量0.5%。在最优工艺参数下,废弃纤维/热塑性聚氨酯保温阻燃复合材料的热传导系数为0.159 W/(m·K),拉伸强度为2.17 MPa,极限氧指数为30.27%。     

黄麻纤维/ES纤维复合材料制备及力学性能分析

将黄麻纤维与ES纤维通过针刺非织造工艺制备成非织造布,再经过热压工艺制备成黄麻纤维/ES纤维复合材料,分析了黄麻纤维/ES纤维质量比和黄麻纤维碱处理对复合材料力学性能的影响。通过试验发现,复合材料的拉伸强度与弯曲强度都随复合材料中黄麻纤维的质量分数增加而呈现出先增加后减小的趋势;对于黄麻原麻/ES复合板材,比例为15/85、20/80时,其拉伸强度和弯曲强度最大,纵、横向拉伸强度达到33.69、28.43 MPa,纵、横向弯曲强度达到最大值36.28、31.75 MPa;对于黄麻碱处理/ES复合板材,比例为25/75、30/70时,其拉伸强度和弯曲强度最大,纵、横向拉伸强度最大达到41.06、39.47 MPa,其纵、横向弯曲强度达到最大值49.96、40.38 MPa。试验表明,碱处理提高了黄麻纤维和ES纤维之间的相容性,提高了界面结合强度,碱处理后的黄麻纤维增强ES纤维复合材料的力学性能优于未处理前。     

阻燃型废弃麻纤维/聚乳酸复合材料的性能分析

以聚乳酸颗粒为基体材料,以废弃麻纤维为增强材料,采用双辊混炼法和热压成型法,制备阻燃型废弃麻纤维/聚乳酸复合材料,并研究其力学性能和阻燃性能,优化其热压工艺参数。以拉伸强度、弯曲强度、冲击强度、极限氧指数为检测指标,以聚乳酸质量分数、阻燃剂质量分数、热压压力、热压温度为因素,通过正交试验和极差分析,优化出最优成型工艺条件,即聚乳酸质量分数为60%,阻燃剂质量分数为30%,热压压力为10 Mpa,热压温度为180℃。为进一步开发阻燃型废弃麻纤维复合材料提供理论基础。     

碳纤维/聚丙烯/聚乳酸增强复合材料的力学性能

为在不改变碳纤维/聚丙烯(PP)复合材料力学性能前提下,降低复合材料中PP含量以减轻环境降解压力,通过在碳纤维/PP复合材料树脂体系中掺杂可降解的聚乳酸(PLA)形成共混树脂体系,并经热压成型制备碳纤维增强共混树脂复合材料。探究了PLA、PP共混体系质量比对复合材料冲击、弯曲和拉伸性能的影响。结果表明:随着树脂体系中PLA质量分数的增加,复合材料的冲击强度和弯曲强度都呈先降低后升高、再降低的趋势,拉伸强度呈现先升高后降低的趋势;当PLA质量分数为60%时,复合材料的冲击强度和弯曲强度最高,分别为21.8 k J/m²和112.5 MPa,拉伸强度为37.2 MPa,复合材料的综合物理力学性能最优,与未添加PLA的复合材料的力学性能相近。     

废弃麻纤维/聚氨酯隔声阻燃复合材料的制备及其性能

以废弃麻纤维为增强材料、废弃聚氨酯为基体材料,添加铁粉和阻燃剂,用共混塑炼-热压法制备废弃麻纤维/聚氨酯隔声阻燃复合材料。通过正交试验及极差分析,优化得到其最佳工艺条件:废弃麻纤维长度6 mm,废弃麻纤维质量分数15.0%,热压温度180℃,阻燃剂质量分数10.0%,铁粉质量分数18.0%。最优工艺条件下,废弃麻纤维/聚氨酯隔声阻燃复合材料的隔声量最高为38.52 d B,具有良好的隔声效果;氧指数为30.00%!32.00%,达到难燃标准;而且,力学性能优良。     

PLA/黄麻多层混纤热压复合材料的制备及工艺优化

以混纤比为30/70的PLA/黄麻混纤针剌絮片为基材,利用热压工艺,制备多层混纤复合材料。以了解热压温度、铺向角等制备工艺参数对多层混纤复合材料力学性能的影响。经优化分析,分别得出弯曲强度、拉伸强度与热压温度、铺向角的回归方程;在此基础上,确立了PLA/黄麻多层混纤复合材料的制备工艺。结果表明:在压强为8MPa、热压时间为3min的情况下,当热压温度为206℃、铺向角为45°时制备得到的多层混纤复合材料力学性能较佳。     

不同成型工艺棕叶纤维/PHBV复合材料的力学性能

研究了精细化棕叶散纤维/PHBV热压复合、棕叶纤维针刺非织造布/PHBV热压复合、棕叶纤维粉末/PHBV共混复合材料的力学性能。以拉伸强度、冲击强度、弹性模量、断裂伸长率为指标探讨了PHBV质量分数、热压压强的影响,并通过SEM观测了复合材料的拉伸断面形貌。结果表明:当PHBV质量分数相同时,棕叶纤维针刺非织造布/PHBV热压复合材料的力学性能最佳,且PHBV质量分数的最优值为35%;当热压压强为13.5 MPa时,热压复合材料可获得最佳的拉伸与冲击性能;棕叶纤维针刺非织造布/PHBV热压复合材料的拉伸断面光滑,少有纤维从基质中拉出;棕叶纤维粉末/PHBV共混复合材料的拉伸断面中存在一定的团聚现象,导致PHBV的包裹性变差,结合力降低。     

黄麻纤维非织造布增强不饱和聚酯树脂复合材料力学性能研究

为了探讨黄麻纤维非织造布/不饱和聚酯树脂复合材料的力学性能,将黄麻纤维通过针刺工艺制备成非织造布,并对其进行碱处理,制备了不同黄麻纤维质量分数的复合材料,测试了复合材料的拉伸弯曲性能,并采用扫描电镜测试了复合材料的断面形态,分析了黄麻纤维针刺非织造布质量分数与碱处理对复合材料拉伸强度与弯曲强度的影响。结果表明:黄麻纤维针刺非织造布对不饱和聚酯树脂的力学性能具有明显的增强效果,且随着黄麻纤维质量分数的增加,复合材料的力学性能先增加后减小,当黄麻纤维/树脂质量比为20/80时,复合材料的拉伸强度和弯曲强度均达到最大,其中碱处理黄麻纤维针刺非织造布增强复合材料的拉伸强度为41.78 MPa,弯曲强度为59.03 MPa;碱处理后黄麻纤维的表面性能得到改善,使得黄麻纤维与聚酯树脂的界面结合情况得到改善,从而提升复合材料的力学性能。     

制备工艺对黄麻纤维针刺非织造布增强PHBV复合材料力学性能的影响

将黄麻原麻通过碱处理后,制备成黄麻纤维针刺非织造布,再采用热压工艺制备成黄麻纤维针刺非织造布增强PHBV复合材料。选取黄麻纤维质量分数、热压温度、热压压强、热压时间4个工艺参数,探讨其对黄麻纤维针刺非织造布增强PHBV复合材料的性能影响。经测试分析得出最佳工艺参数为:黄麻纤维质量分数为40%、热压温度为170℃、热压时间为5 min、热压压强为11 MPa。在此工艺下制备的黄麻纤维针刺非织造布增强PHBV复合材料的拉伸断裂强度达到79.483 MPa。     

热压成型工艺对黄麻／大豆分离蛋白复合材料降解性能的影响

采用热压成型工艺制备黄尉大豆分离蛋白完全可降解复合材料,利用正交试验以质量损失率和拉伸强度损失率为优化指标,研究热压成型工艺因素——成型温度、成型压强和成型时间对复合材料降解性能的影响。试验结果表明,黄彬大豆分离蛋白复合材料的成型温度对其降解性能影响最大,成型压强和成型时间影响较小;在成型温度100℃、成型压强9MPa...     

黄麻/大豆分离蛋白复合材料的制备与性能

采用非织造工艺结合热压工艺制备了完全环境友好型绿色复合材料———黄麻/大豆分离蛋白(SPI)复合材料。利用正交试验法研究了黄麻毡面密度、SPI质量分数和丙三醇含量对黄麻/SPI复合材料断裂强度的影响。试验结果显示,用黄麻与SPI制备的复合材料,其断裂强度大大提高,分别比SPI薄膜和黄麻毡提高了约9倍和29倍。在黄麻毡面密度为550 g/m2,SPI质量分数为11.5%,丙三醇体积分数为7%条件下制备的黄麻/SPI复合材料的断裂强度达到14.22 MPa。     

The impact of adhesive resin solution on carbon fibers cloth and jute-reinforced epoxy resin matrix composites

In this study, a new fiber-reinforced composite material with jute fabric on the surface has been prepared by four layers of carbon fiber fabric (carbon fiber was unidirectional), one layer of jute fabric as strengthen body and E51 epoxy resin as matric through hand lay-up molding process. The orthogonal test was conducted based on three factors of A: (content of T31 curing agent), B: (content of polyamide203#), and C: (content of methyl silicone oil) and each factor has three different values. Instron3369 type universal material testing machine is used to evaluate the tensile and bending properties of the test specimen, and an impact testing machine (Dynatup9250HV type) was used to test the samples’ shock resistance. After orthogonal test and a serious different analysis, the optimal parameters can be created by adhesive resin solution containing 25% curing agent, 10% deforming agent, and 0.3% polyamide203#.     

A new assessment on mechanical properties of jute fiber mat with egg shell powder/nanoclay-reinforced polyester matrix composites

ABSTRACT

Natural fiber polymer matrix composites occupy the major percentage in applications due to its ecofriendly and low-cost nature. This study investigates the mechanical properties of a polyester matrix nanocomposite reinforced by the NaOH-treated jute fabric mat (NJM) and untreated jute fabric mat (UJM). In addition, the effects of egg shell powder (ESP) and nanoclay (NC) to the above has also been studied. The matrices were prepared with different combinations of presence and absence of the ESP, NC, and both as well as different weight percentage using compression molding process. The mechanical and morphological properties of the composites were determined. The tensile strength, flexural strength, and impact strength of NJM with NC 1.5%wt and ESP 1.5%wt were found to be 29.28 MPa, 39.51 MPa and impact strength 3.03 J, respectively. This composition is superior to the other compositions. Morphological analysis of tensile fractured surface showed interfacial adhesion between UJM and NJM composites. NJM composites contained smaller amount of pullouts and the splits compared with the UJM composites, which hold up the better performance.     

Studies on Mechanical and Morphological Characterization of Developed Jute/Hemp/Flax Reinforced Hybrid Composites for Structural Applications

In the present study, an attempt has been made to develop and characterize natural fiber-based composites (jute/epoxy, hemp/epoxy, flax/epoxy) and their hybrid composites (jute/hemp/epoxy, hemp/flax/epoxy, and jute/hemp/flax/epoxy) using hand-lay-up technique. Mechanical characterization (tensile, flexural, impact, and hardness test) of the developed composites was performed. The interface between fiber and matrix was examined using scan electron microscopy (SEM). Among (jute/epoxy, hemp/epoxy, flax/epoxy), flax/epoxy composite has shown higher hardness (98 Shore-D) and tensile strength (46.2 MPa) whereas better flexural and impact strength have been shown by hemp/epoxy (85.59 MPa) and jute/epoxy (7.68 kJ/m²) composites respectively. Results showed that hybrid composites observed better mechanical properties. Jute/hemp/flax/epoxy hybrid composite showed the highest tensile strength, modulus and impact strength of 58.59 MPa, 1.88 GPa, and 10.19, kJ/m², respectively. Jute/hemp/epoxy hybrid composite achieved the maximum flexural strength of 86.6 MPa.     

玄武岩纤维增强复合材料的制备及有限元分析

选取玄武岩纤维作为增强材料,聚丙烯(PP)为基体材料,采用模压工艺制备复合材料。采用单因子试验法研究了温度、压力及保压时间对玄武岩/PP复合材料力学性能的影响,结果表明:不同工艺条件对复合材料的力学性能有很大的影响,在成型温度190℃、成型压力10 MPa、保压时间10 min时制备的复合材料力学性能最佳,此时拉伸强度为267 MPa。运用有限元分析软件对最佳工艺条件下制备的复合材料进行拉伸过程计算机模拟,得出材料的模拟拉伸变形图,并与实际拉伸情况进行对比。有限元模拟表明,断裂发生在试件的平直段端部附近,采用此最佳工艺制备玄武岩/PP复合材料具有可靠性。     

黄麻/豆腐渣/淀粉复合材料的制备及其性能

以黄麻纤维为增强体,经NaOH改性后的豆腐渣/淀粉混合溶液为基体,通过湿法模压制备黄麻/豆腐渣/淀粉复合材料。利用正交试验设计方案研究了豆腐渣/淀粉复配比、黄麻纤维含量、热压温度、热压强度、热压时间对复合材料板材拉伸性能和亲水性能的影响。结果表明：当豆腐渣/淀粉复配比为3、黄麻纤维含量为20%、热压强度为6Mpa、热压温度为80℃、热压时间为2min时,复合材料板材的拉伸断裂强度最优。试验所制备的复合材料片材亲水性较好,表明其具有较差的耐水性能。     

可降解黄麻/PBS复合材料的结构与力学性能

为解决当前环境污染和可持续发展问题,采用模压成型工艺制备可降解黄麻/PBS复合材料,通过拉伸、弯曲性能测试、红外分析和SEM观察,探讨纤维含量和碱处理对材料性能的影响。结果表明:随着纤维含量的增加,复合材料的拉伸强度先增大后减小,在纤维含量为10%时达到最大值,比纯PBS提高了30.1%;拉伸模量、弯曲强度和弯曲模量均随纤维含量的增大而提高,在纤维含量为30%时分别比纯PBS提高了24.2%、185.5%和107.7%。碱处理后黄麻纤维表面杂质被去除,表面部分刻蚀变粗糙,复合材料的综合力学性能得到提高,其中弯曲模量提高显著,比未处理的黄麻复合材料提高了58%。     

Reactive dyeing of a pretreated jute fabric using minimum application technology

Abstract

Grey jute fabrics were given pretreatment such as scouring which was followed by enzyme treatment. These pretreated jute fabrics were subsequently bleached with hydrogen peroxide. Dyeing of these bleached jute fabrics was carried out with four different classes of reactive dyes, namely cold- brand, hot-brand, vinyl sulphone and HE-brand reactive dyes, following the conventional exhaust method and pad-batch method, i.e. minimum application technology method. With respect to dyeing behaviour, it was found that dye uptake and wash fastness property of a dyed fabric produced by the pad-batch method is well comparable with that produced by the conventional exhaust method. Irrespective of the methods of dyeing, scoured–bleached and scoured–enzyme treated–bleached jute fabrics show better dye uptake and fastness property compared to grey-bleached fabrics. Weight loss and strength loss increase while bending length decreases with the increase in pretreatment stages. Enzyme treatment of a scoured jute fabric before bleaching produces the minimum bending length among all the samples. The pretreatment process is found to have some detrimental effect on the tensile properties of a jute fabric and as the number of pretreatment steps increases, the tenacity of the fabric decreases. Reactive dyeing of pretreated jute fabrics further reduces their tensile strength by around 10% irrespective of the method of dyeing and the pretreatment process. So, minimum application technology can be well adopted for dyeing of a jute fabric with reactive dyes. The process is simple, cost effective as it utilises dye to its maximum extent, requires minimum energy and is suitable for use in cottage and small-scale industries.     

防水透湿PU膜层压复合机织物的性能研究

以涤纶机织物、热熔胶TPU(热塑性聚氨酯)弹性体和高透PU(聚氨酯)膜为基材,采用层压复合的方法制备防水透湿复合织物,测试涤纶机织物、高透PU膜及复合织物的拉伸、悬垂、透气及防水透湿性能,讨论不同TPU用量、温度及复合压力对复合织物各项性能的影响。研究结果表明:涤纶机织物与PU膜复合后,在一定程度上能提高复合织物的拉伸断裂强力,但悬垂性比涤纶机织物有所降低,防水效果明显比涤纶机织物要好,透湿、透气效果比高透PU膜要小。当TPU用量为22 g/m2,复合压力为5MPa,复合温度为80℃时,复合织物的复合效果最好。