废弃白麻石粉/橡胶的力学性能研究

将山东白麻花岗岩进行粉碎细化,采用不同的偶联剂对白麻石粉进行活化制备白麻石粉/橡胶复合材料.研究了偶联剂的种类、用量及石粉添加量对复合材料力学性能的影响.结果表明:采用5.0%的硬脂酸改性白麻石粉,在100份橡胶中填加30份白麻石粉后,复合材料的力学性能最佳.活化后白麻石粉具有优异的补强效果及理想的加工特性,可替代炭黑...     

聚乙烯/废天然橡胶的力学性能和相容性研究

利用开放式塑炼机和平板硫化机制备了聚乙烯/废天然橡胶的共混物。研究了聚乙烯/废天然橡胶(60/40)中硫磺加入量对共混物的拉伸强度、伸长率、熔体流速性能的影响。试验结果表明:当聚乙烯/废天然橡胶(60/40)时,硫磺加入1.0份时其综合性能最佳,共混物的拉伸强度达到9.3MPa,断裂伸长率为344%,熔体流动速率为0.25g/10min。     

漂珠改性天然橡胶复合材料的性能研究

利用Si-6偶联剂改性漂珠,通过直接共混法将改性的漂珠和NR制备漂珠/NR复合材料.研究复合材料的拉伸性能、硬度、热性能变化规律,并利用SEM研究试样拉伸断裂机理.结果表明:改性后漂珠的粒径减小,呈不规则的块状结构.与半补强炭黑/NR相比,漂珠/NR复合材料的断裂伸长率提高,拉伸强度未见变小,硬度减小.价格低廉的漂珠能替代炭黑作橡胶补强材料.     

超声波对F-12/环氧复合材料力学性能的影响

界面强度较弱是影响芳纶/环氧复合材料力学性能发挥的重要因素。本文采用超声技术在F-12/环氧浸润过程中增加树脂对纤维的浸润性, 从而改善复合材料的界面性能。探讨了超声最佳处理参数, 着重研究超声对复合材料力学性能的影响。      

石墨烯/聚氨酯复合材料的制备及其力学性能分析

采用聚四氢呋喃作为软段,2,4-甲苯二异氰酸酯为硬段,MOCA为扩链剂,物理剥离的石墨烯(GNs)和硅烷偶联剂(APTES)改性的氧化石墨烯(GO)为填料合成了石墨烯/聚氨酯复合材料。通过溶胀平衡实验探究石墨烯与聚氨酯基体的相容性对力学性能的影响。结果表明,两种石墨烯的加入均能提高复合材料体系的交联密度。复合材料的拉伸强度均先增大后减小,损耗因子峰值增大。但改性GO能使阻尼温域拓宽,并且随着添加量的增加,改性GO组的体系交联密度、溶胀比、拉伸强度保持率等均优于GNs组。     

PVC/重晶石纳米复合材料力学性能与形态研究

研究了新型无机功能填料——纳米硫酸钡(nano-BaSO4)的表面处理及添加量对聚氯乙烯(PVC)力学性能的影响以及纳米粒子在PVC基体中的分散情况。结果表明,添加1%经过硬脂酸处理的纳米硫酸钡可以对PVC基体产生显著的增韧补强作用,其冲击断面呈现明显的韧性断裂特征。且SEM微观形貌观察表明,纳米粒子在PVC基体中分散良好。     

拉伸速率对PP/GB复合材料力学性能的影响

应用Instron材料试验机考察了室温下拉伸速率对玻璃微珠填充聚丙烯复合材料的弹性模量和屈服强度的影响，结果表明，随着微珠含量的增加，试样的弹性模量（Ec）增大，且与拉伸应变速率呈近乎幂律函数关系，而屈服强度（бyc）则随着微珠体积分数（Φf）的增加呈线性函数形式下降，并随着拉伸应变速率的增加呈幂律函数形式提高，此外，讨论了Ec、Φf与бyc三者之间的关系。     

纳米氧化锌改性胶粉/天然橡胶复合材料的制备及性能

利用纳米氧化锌采用直接混合、球磨分散混合及超声分散混合法对胶粉进行了改性．并在开炼机上制备了纳米氧化锌改性胶粉／天然橡胶复舍材料。利用扫描电镜对纳米氧化锌的分散效果进行了考察，并测试了填充改性胶粉的天然橡胶复合材料的拉伸性能、撕裂强度及耐磨性。结果表明，超声分散混合法得到的试样中纳米氧化锌的分散情况较好，其中采用钛酸酯偶联剂改性的试样的性能最佳，与纳米氧化锌直接混合和添加活性氧化锌的试样相比其拉伸强度分别提高32％和55％，扯断伸长率分别提高7％和22％，撕裂强度分别提高28％和39％．耐磨性分别提高17％和7％。     

界面层对CVI-mini SiCf/SiC复合材料力学性能的影响

利用化学气相渗透法(CVI)在束丝SiC纤维表面沉积BN和BN/SiC两种界面层,并将其制备成mini碳化硅复合材料.应用扫描电镜(SEM)观察了界面层和mini复材的表面和断口形貌,应用原子力显微镜(AFM)表征了界面层的表面粗糙度.采用X射线衍射(XRD)和透射电镜(TEM)对界面层结构进行表征,利用电子万能试验机对mini复材的拉伸性能进行分析.结果表明,CVI方法制备的BN表面光滑,为层状-岛状生长,与基体结合较弱,其mini复材拉伸强度为970 MPa.热处理后的BN结晶度增强,表面粗糙度增大,与基体的结合略微增强,其mini复材拉伸强度有所提升,为1050 MPa.BN/SiC界面层表面粗糙,为岛状生长,与基体的结合较强,其mini拉伸强度最高,为1720 MPa.     

CaCO3/PP复合材料的制备及力学性能研究

采用钛酸酯偶联剂对CaCO3粒子进行表面处理,通过双辊熔融共混和硫化压机压片技术制备了CaCO3/PP复合材料;测试了其拉伸强度、冲击强度和硬度,探讨了偶联剂用量和CaCO3添加量对复合材料力学性能的影响.研究表明,添加CaCO3粒子能有效提高PP材料的力学性能,且经偶联剂表面处理后的CaCO3粒子对改善PP的力学性能效果更佳,当采用2%钛酸酯偶联剂表面处理后的CaCO3粒子添加量为4%时,CaCO3/PP复合材料综合力学性能最好.     

天然橡胶/羧甲基壳聚糖抗菌复合膜的力学性能研究

采用胶乳共混法制备得到了天然橡胶羧甲基壳聚糖(NR/CCS)复合胶膜,通过NMR交联密度仪、拉力测试机、动态热力学分析仪等对复合材料的性能进行了表征。结果表明,复合胶膜的交联密度略微增大(5.75×10-5mol/cm3),力学性能增强到11.25MPa,并且复合胶膜的弹性模量增大,刚性增强,并通过这些测试证明了NR与CCS分子存在氢键的作用。     

改性天然胶乳/壳聚糖/明胶三元复合材料制备研究

采用正交试验方法,考察了原料的配比、交联剂的用量及交联温度等对复合材料性能的影响。较佳的制备工艺条件分别为改性天然胶乳/壳聚糖/明胶配比60/20/20,交联剂用量0.004%,交联温度60℃。随改性天然胶乳的加入,复合膜柔韧性增强,力学性能下降;壳聚糖对复合膜的力学性能贡献大于明胶。     

The impact of esterification on the properties of starch/natural rubber composite

The starch was modified by esterification, and the starch/natural rubber composite was prepared by blending the modified starch with natural rubber latex. The morphology, thermal stability and mechanical properties of the composite were investigated. The results show that the crystal structure of starch in the composite disappears after modification with esterification, and the starch particles with an average size around 200 nm homogenously disperse throughout the natural rubber (NR) matrix. The thermal stability of composite is improved significantly after the modification with starch. The mechanical properties of composite are enhanced with the increase of starch loading. The composite possesses the best properties at the starch xanthate content of 20 parts per hundred rubber (phr). The enhanced thermal stability and mechanical properties of modified starch/NR composite are mainly due to the improved phase interface interactions between rubber and starch.     

Mechanical reinforcement in natural rubber/organoclay nanocomposites

Aim of this work is to get an insight into the mechanisms by which nanofillers produce mechanical reinforcement in polymers above their glass transition temperature. To this purpose, the mechanical behaviour of natural rubber/organo-modified montmorillonite vulcanisates produced by melt mixing with various filler contents was investigated. Data of the initial modulus, evaluated from stress–elongation curves obtained in tensile tests carried out at room temperature and a fixed cross-head rate, were analysed as a function of the organoclay content by applying mechanical models proposed in the literature. Such analysis provided an evaluation of the filler percolation threshold. Further, tests performed with varying temperature and rate pointed out appreciable rate and temperature dependence only for samples containing amounts of organoclay higher than the percolation limit, that is in presence of filler networking. Such a typical viscoelastic behaviour associated to the presence of the filler network contributes to support the hypothesis that in filled rubbers the mechanisms of filler networking is based on the formation of confined regions of immobilised polymer that join the filler particles of the network, as recently proposed.     

过氧化物预硫化天然橡胶/丝素蛋白抗菌复合材料的制备与性能研究

采用三元混合体系溶解丝素蛋白,纯化后与过氧化物预硫化天然橡胶复合,得到了具有抗菌性能的天然橡胶/丝素蛋白(PVNR/SF)复合材料,并对胶乳和胶膜的相关性能分别进行测试分析。结果表明,SF的加入保持了天然胶乳的稳定性。在干燥制成胶膜后,与基体材料有很好的相容性,并且可以在一定程度上起到补强的作用,SF使天然橡胶获得良好的抗菌性能的同时,对基体的热稳定、粘弹等性能没有很大的影响。另外,通过红外光谱我们可以推测SF在胶膜中的抗菌性能与酰胺I结构有关。     

环氧化天然橡胶改性石墨烯-炭黑/天然橡胶复合材料的制备及性能

以环氧化天然橡胶(ENR)为界面改性剂,制备了石墨烯-炭黑/天然橡胶-ENR(GR-CB/NR-ENR)复合材料,研究了ENR用量对GR-CB/NR-ENR复合材料的加工性能、力学性能和动态力学性能的影响。结果表明,ENR的加入可以改善GR-CB/NR-ENR复合材料的加工性能及CB粒子在天然橡胶基体中的分散性,增加GR与NR的相容性,增强填料与NR基体间的界面相容性,同时改善GR-CB/NR-ENR硫化胶的动态力学性能、物理性能和耐老化性能。当ENR添加量为6 wt%时,GR-CB/NR-ENR复合材料撕裂强度和拉伸强度最高,硫化胶耐老化性最好。随着ENR含量的增加,GR-CB/NR-ENR复合材料的压缩疲劳温度先升高后降低;随着应变的不断增大,GR-CB/NR-ENR复合材料的储能模量G'不断减小,损耗因子tanδ先增大后减小;动态模量随着应变的增加急剧下降。      

Structure and properties of polylactide/natural rubber blends

Polylactide, PLA, is a biodegradable thermoplastic polyester derived from biomass that has restricted packaging applications due to its high brittleness and poor crystallisation behaviour. Here, new formulations based on natural rubber–PLA blends have been developed. The processing windows, temperature, time, and rotor rate, and the rubber content have been optimised in order to obtain a blend with useful properties. The rubber phase was uniformly dispersed in the continuous PLA matrix with a droplet size range from 1.1 to 2.0 μm. The ductility of PLA has been significantly improved by blending with natural rubber, NR. The elongation at break improved from 5% for neat PLA to 200% by adding 10 wt% NR. In addition, the incorporation of NR not only increased the crystallisation rate but also enhanced the crystallisation ability of PLA. These materials are, therefore, very promising for industrial applications.