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。     

阻燃型玄武岩织物/聚乳酸复合材料的研制

采用热压法成型工艺制备了阻燃型玄武岩织物增强聚乳酸复合材料,考察了聚乳酸质量分数、热压压力、热压温度、阻燃剂质量分数对复合材料拉伸强度、弯曲强度及极限氧指数的影响,通过正交实验、极差分析及单因素分析,优化出制备阻燃型玄武岩织物增强聚乳酸复合材料的最优工艺：阻燃剂质量分数30%,聚乳酸质量分数64.6%（5：7）,热压压力5MPa,热压温度185℃。结果表明：添加氢氧化镁阻燃剂制备的阻燃型玄武岩织物增强聚乳酸复合材料,力学性能较未添加阻燃剂的玄武岩织物增强聚乳酸复合材料有所降低,但仍比较优异,且极限氧指数可提高到35.2%。     

亚麻纤维增强聚乳酸复合材料的制备与性能表征

针对预成型件的铺层角度对复合材料力学性能产生影响的问题,以亚麻纤维为增强体,与聚乳酸纤维通过开松、混合、梳理工序制成预成型件后,采用模压成型工艺制备了亚麻纤维/聚乳酸复合材料。研究预成型件的各种铺层角度对复合材料拉伸、弯曲性能的影响,并通过扫描电镜讨论亚麻/聚乳酸复合材料的破坏机制以及拉伸断裂形貌。结果表明：铺层角度为90°时,复合材料横向拉伸、弯曲强度和模量最高;铺层角度为0°时,复合材料纵向拉伸、弯曲强度和模量最高。     

麻纤维复合材料的结构设计与加工

通过自行设计的积木式模具,设计加工出不同立体结构的高性能麻纤维与热塑性树脂复合材料。在确定合适的成型工艺的基础上,探讨了模压成型工艺参数对产品力学性能的影响。最后对不同结构复合材料的力学性能进行了分析。     

碱处理对旧报纸纤维/聚乳酸复合材料力学性能的影响

利用注射成形工艺制备了旧报纸纤维(NRF)/聚乳酸(PLA)复合材料,探讨了碱处理对NRF/PLA复合材料力学性能的影响。结果表明,碱处理可使旧报纸纤维中部分半纤维素和果胶等物质溶出,纤维表面极性降低,旧报纸纤维与聚乳酸相容性得到改善;碱处理后的旧报纸纤维纤维素结晶度增大,纤维表面孔径增大,比表面积增加,纤维表面油墨被去除,旧报纸纤维与聚乳酸界面结合性能得到改善,NRF/PLA复合材料力学性能提高。     

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。     

蔗渣纤维增强聚乳酸复合材料的制备及性能分析

以造纸用蔗渣纤维和聚乳酸(PLA)为主要原料,制备了蔗渣纤维增强聚乳酸复合材料,研究了NaOH(蔗渣纤维处理剂)的质量分数、复合材料中蔗渣纤维添加量及热压温度对复合材料力学性能的影响。结果表明,蔗渣纤维添加量为30%时,蔗渣纤维与PLA混合较好,复合材料较均匀;采用质量分数为5%的NaOH处理蔗渣纤维,可以溶解蔗渣纤维中的半纤维素、果胶等,使纤维更细化,比表面积增大,从而有效改善复合材料力学性能;热压温度为170℃时,PLA的流动性有助于改善蔗渣纤维在PLA中分散的均匀性,且不会使蔗渣纤维和PLA降解。在此最优条件下,复合材料的拉伸强度和冲击强度分别达到最大值。     

柞蚕丝素/聚乳酸复合材料的制备及其性能研究

采用磷酸水解法提取柞蚕茧壳中的柞蚕丝素,用二氯甲烷溶解聚乳酸制备聚乳酸/柞蚕丝素复合材料,并对复合材料的力学性能、可降解性能、水溶性进行测定。测定结果为:水解时间为1h、粒径为15μm、PEG(400)含量为0%、柞蚕丝素添加量为5%时,柞蚕丝素/聚乳酸复合材料具有较高的机械强度,且无毒无害、可环境降解,应用前景十分可观。     

麻纤维的改性及其增强复合材料的研究现状

对常见的几种麻纤维与高性能化学纤维的性能进行简单对比,详述了麻纤维表面改性的研究现状。介绍了国内外麻纤维复合材料的应用情况,指出麻纤维增强复合材料具有广泛的应用前景。     

聚乳酸酯PLA纤维的性能

简要介绍了聚乳酸酯（PLA）纤维的发展现状,重点研究了聚乳酸酯纤维的物理和功能性指标,结果表明,聚乳酸酯纤维具有抗菌、阻燃、易染色等特性,是一种可生物降解的绿色环保纤维。     

Microfoaming of flax and wood fibre reinforced polypropylene composites

Natural and wood fibre reinforced plastics as a relatively new group of environmental friendly materials have been extensively applied in interior, building applications and in the automobile industry. Among others, natural and wood fibre reinforced foamed polymer materials are of high significance because of the possibility of their reducing the density of automotive components which have a cellular structure. However, the properties of these materials have not been fully investigated and described. Microcellular composites of polypropylene containing natural and wood fibre was prepared using an injection moulding process. In the present work, the manufacturing technology of natural and wood fibre reinforced polymer microfoams was developed and the influence of fibre and microvoid content on its property spectrum was systematically investigated. The forming of microvoids and the degree of foaming related to the variation of the processing parameters in connection with manufacture technology was characterised. Measurement of density, cell size, tensile and flexural properties of the prepared composites was carried out. The cell structure is dependent on flow direction of foaming. The density of microfoamed wood fibre-PP composites was reduced by about 24% and decreased by as much as 0.77 g/cm³.Light microscopy showed that the cells are circular and it was also observed that the maximum cell sizes are between 10–50 μm. Water absorption and scanning electron microscopy of the composites were also investigated. Considering the experimental results, it can be deduced that the microcellular composites exhibit a possible combination of relatively good engineering properties and lower density for different technical applications.     

聚乳酸纤维织物服用性能测试与分析

为更好地了解聚乳酸纤维织物的服用性能,提高产品开发的针对性,对相近规格的纯聚乳酸纤维织物、聚乳酸纤维/棉(80/20)混纺织物、棉织物、涤纶织物进行强伸度、透气性、折皱回复性、导湿性、悬垂性、耐磨性、起毛起球性、交织阻力等性能的测试。结果表明:聚乳酸纤维织物具有很好的伸长变形能力;其折皱回复性、导湿性、悬垂性和耐磨性良好;透气性和抗起毛起球性不如棉织物;具有较高的交织阻力,可防止织物产生纰裂。聚乳酸纤维/棉混纺织物由于棉纤维的加入改善了聚乳酸纤维织物的透气性和抗起毛起球性,减小打纬阻力,但织物的折皱回复性、悬垂性和耐磨性有所降低。     

玄武岩织物增强聚乳酸复合材料的制备及其拉伸断裂性能

为提高聚乳酸复合材料的力学性能,以玄武岩织物(BF)为增强材料,聚乳酸(PLA)为基体材料,采用真空灌注法制备玄武岩织物增强聚乳酸复合材料。研究了偶联剂KH550质量分数、铺层层数、铺层角度对BF/PLA复合材料拉伸断裂性能的影响,并借助扫描电子显微镜对复合材料拉伸实验后的断裂形貌图进行分析。结果表明:随着KH550质量分数的增加,BF/PLA复合材料的拉伸断裂强度出现先增大后减小的趋势,且KH550质量分数为3%时处理效果最佳,此时复合材料的拉伸断裂强度提高到82 MPa,且断面整齐;玄武岩织物铺层角度为0°和90°时,复合材料的拉伸断裂性能较优,45°铺设时最差,且拉伸实验后层间分离现象明显;在一定范围内复合材料的断裂强度随玄武岩织物铺层层数的增加而增加。     

Lyocell/亚麻混纺织物盐酸法定量分析

采用盐酸法对Lyocell/亚麻混纺织物进行化学定量分析,研究盐酸浓度、浴比、振荡时间、振荡频率和水浴温度等因素对两种纤维含量测定结果的影响.通过正交试验,确定优化的测定参数为:盐酸质量浓度1.178 g/mL,水浴温度25℃.处理时间15 min,振荡速率150 r/min,浴比1:200.用盐酸法定量分析测定Lyocell和亚麻含量,准确、高效、简便.     

3D打印成型的玻璃纤维增强聚乳酸基复合材料

为解决3D 打印树脂基材料强力低的问题,提出利用纤维增强树脂基材料的方法,采用3D 打印技术将玻璃纤维和聚乳酸复合并且快速成型,并研究了填充密度和切片层厚对于复合材料力学性能的影响。试验结果表明,当试样打印的填充密度达到90%时,试样的弯曲强度和拉伸强度分别可达到49.26和21.28MPa。试样切片层厚为0.1 mm时,所得到的拉伸强度和弯曲强度分别为20.4 和52.87 MPa。试样的拉伸强度随着切片层厚的增加而减少,随着填充密度的增加而增加。试样的弯曲强度与切片层厚是负相关,与填充密度是正相关。通过分析不同种类试样截面的扫描电镜图发现,纤维束浸润树脂基体的程度与试样的层厚和填充密度密切相关,填充密度的增加和层厚的减少有利于纤维束与树脂基体的结合。     

竹原/亚麻复合材料力学性能的模糊评判

采用竹原纤维、亚麻纤维作为增强体,低熔点聚酯纤维(LMPET)及丙纶纤维(PP)做基体,通过非织造工艺制作混合纤维预成型件,采用模压成型工艺制作植物纤维增强复合材料。用模糊综合评判的方法,探讨增强相与基体相选用的纤维种类及纤维质量百分率对材料力学性能的影响。利用扫描电镜研究了复合材料拉伸断口的形貌。结果表明:LMPET/40%竹原纤维复合材料的力学性能最优,纵、横向拉伸强度分别为136.00 MPa和87.58 MPa;纵、横向弯曲强度分别为534.00 MPa和470.00 MPa,超过了普通工程塑料的水平。     

Chemical,microscopic, and instrumental analysis of graded flax fibre and yarn

A series of flax fibre and yarn samples that had been commercially graded low, medium, and high quality were analysed by light microscopy, wet chemical analysis, Raman spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy to determine characteristics which could be related to quality ratings for each sample type. Light microscopy revealed fragments of cuticular and epidermal material bound to the fibres. As the quality ratings improved, fewer of these fragments were found and greater separation of the fibre bundles to smaller bundles and, in some cases, elementary fibres occurred indicating more efficient retting. Chemical evaluation showed that, as quality of the yarns increased, amounts of fatty acid and long‐chain alcohols as well as dihydroxy fatty acids decreased. Chemical data on fibre did not show consistent trends with quality. Raman spectroscopy showed increasing amounts of cellulose and decreasing amounts of aromatics and hydrocarbons with increasing quality, which paralleled the chemical data. NMR analysis showed nearly equal amounts of crystalline cellulose regardless of quality for both fibre and yarn samples. The strengths and weaknesses of each analytical method are discussed. This initial study suggested that chemical constituents characteristic of cutin and waxes could be used as an initial marker of quality. © 1999 Society of Chemical Industry