混杂复合方式对聚丙烯复合材料性能的影响

利用混杂原理将增强体纤维与基体成分相同的纤维混合针刺,再与基体树脂膜层压复合。通过对复合材料力学性能的测试,讨论了新的复合方式及层压工艺对复合材料力学性能的影响。结果表明,新的复合方式对复合材料的力学性能有较大影响,特别是混杂纤维含量对复合材料力学性能的影响,且混杂复合工艺对复合材料力学性能的影响大于传统复合工艺对复合材料力学性能的影响。     

针刺工艺对玄武岩针刺非织造复合材料性能的影响

以玄武岩针刺非织造织物为增强体,以硼酚醛树脂为基体树脂,采用层压复合工艺制备了复合材料,研究了不同针刺工艺对复合材料力学性能的影响。结果表明,相同针刺工艺条件下,复合材料的拉伸强度随复合层压压力的增加先增大后减小,复合材料的弯曲强度随复合层压压力的增加而线性增强;在一定情况下,增强体的孔隙率对复合材料力学性能的影响高于增强体拉伸强度对复合材料力学性能的影响。     

单向玄武岩增强复合材料工艺与性能研究

采用正交试验方法,以冷却方式、成型压力、增强纤维百分含量、成型温度为影响因素研究以单向布为增强体结构的玄武岩增强硼酚醛树脂复合材料的工艺性能。结果表明,成型温度对复合材料的力学性能影响最大,且随着成型温度的提高而线性增强;增强纤维的百分含量对复合材料拉伸性能的有较大影响,但对弯曲性能的影响较小,且力学性能不随增强纤维含量的增加而线性增强;成型压力的增大有利于复合材料弯曲性能的改善,而对拉伸性能的影响较小;适当延长冷却时间有利于复合材料力学性能的提高。     

剑麻纤维/玄武岩纤维混杂增强聚乳酸复合材料的力学性能研究

混杂纤维增强复合材料由于可以综合利用各种纤维的优点,极大地提高复合材料的性能,拓展复合材料的适用范围。采用剑麻纤维和玄武岩纤维混杂增强聚乳酸制备复合材料,研究了纤维含量和铺层顺序对混杂纤维复合材料力学性能的影响。结果表明,剑麻纤维作为芯层、玄武岩纤维作为表层时混杂复合材料具有较好力学性能。当纤维质量分数为40%时,其拉伸强度和冲击强度比纯聚乳酸分别提高了2.83倍、41.47倍,达到了267.29 MPa和183.46k J/m~2;纤维含量为30%时,其弯曲强度比纯聚乳酸提高4.07倍,达到354.16 MPa。     

聚丙烯自增强复合材料层压板的制备和性能研究

以聚丙烯树脂为基体,聚丙烯纤维织物为增强体,采用层压成型工艺制备了聚丙烯自增强复合材料层压板。研究了成型温度、成型压力、成型时间和纤维含量等工艺参数对聚丙烯自增强复合材料层压板拉伸和弯曲性能的影响规律,并采用差示扫描量热(DSC)仪和扫描电子显微镜(SEM)对其进行了热分析和形态结构的表征。结果表明,当成型温度为175℃,成型压力为10 MPa,成型时间为15 min,纤维含量为60%时,聚丙烯自增强复合材料层压板的力学性能达到最大值,其拉伸强度为(125.76±0.77)MPa,弯曲强度和弯曲弹性模量分别为(30.77±0.70)MPa和(1 795.46±75.95)MPa;从DSC图和SEM图观察到成型温度为175℃时聚丙烯纤维表面发生了熔融,有利于纤维和树脂之间的界面粘结力的增强。     

取向长剑麻纤维增强聚乳酸层压复合材料力学性能的研究

通过溶液浸渍法制备剑麻纤维预浸渍料,然后通过热压成型的方法制备了纤维含量(质量分数)分别为10%、20%、30%和40%的取向长剑麻纤维增强聚乳酸层压复合材料,同时制备了随机取向的短剑麻纤维增强聚乳酸复合材料。研究了不同的纤维含量对取向长剑麻纤维增强聚乳酸层压复合材料力学性能的影响。结果表明,当纤维含量为40%时,复合材料的力学性能最好。其拉伸强度、弯曲强度以及冲击强度比纯聚乳酸分别提高了1.90、1.29以及15.69倍,比短纤维剑麻纤维增强聚乳酸分别提高了4.47、2.27以及10.73倍,达到了164.76、202.88 MPa以及36.72 k J/m~2。     

一种纤维自增强聚乳酸复合材料的成型方法

采用了一种片材包覆层压的方式,制备了聚乳酸(PLA)纤维自增强PLA复合材料,通过力学性能测试、SEM及DSC分析等方法研究了PLA纤维含量、制备方法对自增强PLA材料力学性能、界面结构的影响。结果表明:随着PLA纤维含量的增加,自增强材料的力学性能显著提高;片材包覆层压法与模压成型方法相比较,纤维在加工过程中的受破坏程度较小冲,击性能更高。     

连续玄武岩纤维平纹布增强硼酚醛树脂复合材料研究

对硼酚醛（FB）树脂进行了性能表征,介绍了连续玄武岩纤维平纹布（CBFTC）增强FB树脂复合材料的制备,研究了层压成型工艺对该复合材料力学性能和烧蚀性能的影响。结果表明,当FB树脂质量分数为28％、预固化温度为150℃、固化温度为180℃、固化压力为5MPa、固化时间为15min·mm^-1时,FB／CBFTC复合材料的力学性能和烧蚀性能最好。     

玻璃纤维毡增强聚丙烯在压缩模塑流动过程中的纤维分布

通过测定玻璃纤维毡增强聚丙烯经挤压流动后不同区域的纤维含量,研究了基体树脂,增强材料的结构与性质,坯料设计,模具温度及坯料的预热温度等对玻璃纤维毡增强聚丙烯在压缩模塑流动过程中纤维发布的影响。结果表明,适当提高基体的粘度及采用多层坯料叠层的坯料设计方法,有利于制品内纤维的均匀分布;针刺密度适当的连续针刺毡及由短切纤维组成的复合针刺毡与聚丙烯形成的复合材料（GMT0,在压缩模塑的流动过程中纤维分布的均匀性较好,随着针刺密度的增加,纤维分布的均匀性下降;用粘结剂粘结而成的连续原丝毡与聚丙烯复合得到的GMT材料,纤维分布的均匀性较差,经适当针刺以后,纤维分布的均匀性得到一定程度的改善,过低的模具温度及坯料预热温度,会引起材料充模流动能力下降,但模具温度及坯料预热温度过高时,流动前沿区域的树脂富集现象将加剧。     

AKD改性杨木粉/PLA复合材料模压工艺与性能

以杨木粉和聚乳酸为原料,利用烷基烯酮二聚体(AKD)对杨木粉进行表面改性处理,通过模压成型工艺制备了杨木粉/聚乳酸(PLA)复合材料。以模压温度、模压压力和保压时间为正交实验因素,将复合材料力学弯曲性能和冲击强度作为评价指标,分析了模压成型工艺对复合材料力学性能的影响;在此基础上分析了AKD含量对杨木粉/PLA复合材料力学性能和吸水性能的影响。结果表明,模压工艺对复合材料力学性能的影响程度依次为模压温度、模压压力、保压时间;当模压温度为170℃、模压压力为4 MPa、保压时间为6 min/次、5次保压、AKD含量为2%～3%时,制备的杨木粉/聚乳酸复合材料力学性能和吸水性能较好。     

Mechanical and thermal properties of bamboo fiber reinforced polypropylene/polylactic acid composites for 3D printing

In this article, a kind of degradable composite was prepared from bamboo fiber (BF), poly lactic acid (PLA), and polypropylene (PP). The mechanical and thermal properties were characterized by the universal testing machine, thermogravimetric analysis, differential scanning calorimetry. In order to improve the compability between BF and polymer matrix several modification on the surface of BF were explored and compared. Moreover, a compatibilizer (maleated PP) was applied to further increase compatibility between the fiber and matrix. It is found that the thermal stability of BF/PP/PLA composites decreased with the increase of maleated polypropylene (MAPP) content. When 5% MAPP was used the tensile strength, flexural strength, and impact strength of composites reached 33.73, 47.18 MPa, and 3.15 KJ/m², with an increase by 13, 11.7, and 23.5%, respectively, compared with the composites without MAPP. The improvement of mechanical properties is attributed to the fact that irregular grooves and cracks induced by the modification of BF facilitate the infiltration of polymer into fiber due to the strong capillary effect. Furthermore, BF/PP/PLA composites are potential to be used in 3D printing. POLYM. ENG. SCI., 59:E247–E260, 2019. © 2018 Society of Plastics Engineers     

Polylactic acid (PLA)/banana fiber (BF) biodegradable green composites

In this study, polylactic acid (PLA)/banana fiber (BF) composites were prepared by melt blending method. The BF was conjugated onto PLA chains through the use of a coupling agent and chemical modification. Consequently, the thermal stability and mechanical properties of the PLA were dramatically elevated through the incorporation of BF. Mechanical tests showed that the tensile and flexural strengths of the composites markedly increased with the fiber content, reaching 78.6 and 65.4 MPa when reinforced with 40 phr fiber, approximately 2 and 1.66 times higher, produced by pristine PLA. However, the impact strengths of composites are somewhat decreased with the increased content of fibers. The addition of 40 phr BF into the composite increased the HDT of pure PLA from 62 °C to 139 °C; an improvement of about 122%. Apart from enhancing the mechanical properties and thermal stability, the incorporation of BF can reduce the production cost of materials while meeting the demands of environmental protection agencies.     

Effect of polyethylene glycol on mechanical properties of bamboo fiber-reinforced polylactic acid composites

The bamboo fiber (BF)-reinforced polylactic acid (PLA) composites were prepared using the twin-screw extruder and injection molding. Thermal gravimetric analyzer results indicated the thermal stability of BF/PLA composites decreased with increasing BF content. Differential scanning calorimeter and X-ray diffraction curves showed that BF played a role as a nucleating agent, but the crystallinity of composite materials decreased with the increasing BF content. The melt flow rate of composites reduced with the increase in BF content, resulting in a poorer processing property. The processability of the composites was improved with the addition of high molecular polyethylene glycol (PEG). Mechanics performance test showed that tensile strength and bending strength of composites increased at low loading with the BF content increased then decreased when the loading continued to increase. The tensile strength of the composite materials reached 65.46 MPa when alkali-treated BF (ABF) content was 20 wt %. The flexural strength of the composites reached 97.94 MPa when ABF content was 10 wt %. Impact performance has also been improved. PEG-20000 was the best plasticizer among the PEG-6000,PEG-10000, and PEG-20000. When the component of PEG was 10 wt %, the elongation increased by 56%. The scanning electron microscopy (SEM) result showed that the fracture of the composites was smooth, most ABF were wrapped in matrix and distribution of ABF in PLA matrix was more uniform. It means that interfacial compatibility of bamboo fiber and PLA improved after BF modified by alkali. High molecular weight PEG enhance melt flow ability of polymer, result in fibers were further enclosed in the PLA matrix and increase properties of composites. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47709.     

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.     

BF/CF层间混杂结构对复合材料性能影响

制备了碳纤维/玄武岩纤维(CF/BF)层间混杂增强酚醛树脂基复合材料,通过力学性能测试研究了混杂结构对复合材料性能的影响,并与层数相同叠合压制成型的BF复合材料的性能进行了对比。结果表明,CF/BF混杂纤维增强酚醛树脂基复合材料较BF复合材料力学性能提高,嵌层结构复合材料综合性能好于夹芯结构。     

The Effect of Fiber Bleaching Treatment on the Properties of Poly(lactic acid)/Oil Palm Empty Fruit Bunch Fiber Composites

In this work, biodegradable composites from poly(lactic acid) (PLA) and oil palm empty fruit bunch (OPEFB) fiber were prepared by melt blending method. Prior to mixing, the fiber was modified through bleaching treatment using hydrogen peroxide. Bleached fiber composite showed an improvement in mechanical properties as compared to untreated fiber composite due to the enhanced fiber/matrix interfacial adhesion. Interestingly, fiber bleaching treatment also improved the physical appearance of the composite. The study was extended by blending the composites with commercially available masterbatch colorant.     

蒸汽爆破预处理PLA/剑麻复合材料的性能研究

对剑麻纤维(SF)进行蒸汽爆破预处理,并与可生物降解材料聚乳酸(PLA)经模压成型制备降解复合材料,研究了混炼温度、SF含量及蒸汽爆破预处理对复合材料力学性能的影响,并通过X射线光电子能谱(XPS)和扫描电子显微镜(SEM)分析了其作用机理.结果表明,蒸汽爆破预处理可提高SF纤维素的含量,增大纤维的比表面积,使复合材料...     

连续玻璃纤维增强PLA复合材料3D打印技术研究

以聚乳酸(PLA)为基体,连续玻璃纤维为增强体,采用熔融浸渍工艺制备连续玻璃纤维预浸丝,将制得的预浸丝作为3D打印耗材用于熔融沉积(FDM)的3D技术来制备连续玻璃纤维增强PLA复合材料试样,并研究了打印温度、层厚和打印速度对复合材料力学性能的影响。结果表明,当打印层厚为0. 5 mm,打印温度为230℃,打印速度为2 mm/s时,连续玻璃纤维增强PLA复合材料的弯曲性能最佳,弯曲强度和弯曲模量分别为327. 84 MPa和20. 293 GPa。综合考虑复合材料的力学性能、表面质量和尺寸稳定性,连续玻璃纤维增强PLA复合材料的最佳打印层厚为0. 5 mm,适宜的打印温度范围为200~220℃,打印速度范围为2~4 mm/s。     

Influence of heat treatment on the heat distortion temperature of poly(lactic acid)/bamboo fiber/talc hybrid biocomposites

Influence of heat treatment and fillers on the heat distortion temperature (HDT) of poly(lactic acid) hybrid biocomposites was intensively studied through HDT testing, polarizing microscope (POM), differential scanning calorimetry (DSC), and dynamic mechanical analysis (DMA). With loading 20 wt % BF or 20 wt % talc, improvement of HDT in PLA composite was about 10°C comparing with neat PLA after heat treatment. Moreover, there was a great improvement (above 45°C) of HDT in PLA composites with loading 20 wt % BF and 20 wt % talc simultaneously after heat treatment. Transcrystallization was observed during heat treatment and isothermal crystallization of PLA composites with loading BF and talc simultaneously. There was no similar phenomenon in other PLA composite with loading only one filler. The possible mechanism of forming transcrystallization was proposed. DSC and DMA were also used to clarify the variation in HDT before and after heat treatment, and the results suggest that the crystallinity, modulus and glass transition changed, especially formation of transcrystallization played a key role in improvement of HDT in PLA composites. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012