HDPE／CaCO3复合材料片材制品的力学性能

通过制备不同含量的微米级和纳米级碳酸钙(CaCO3)填充的高密度聚乙烯(HDPE)片材制品,对其力学性能进行分析。研究了微米级和纳米级CaCO3对HDPECaCO3复合材料片材制品的力学性能的影响规律,并对此影响规律进行了合理的解释。     

玉米淀粉/ε-聚己内酯复合片材的制备及结构表征

应用V(丙三醇)∶V(聚乙烯醇)=5∶1组成的复合增塑剂将微细化处理的玉米淀粉于155～170℃热塑化后,与ε 聚己内酯(PCL)于150℃下辊炼压延制备成复合片材。应用拉力试验机、SEM、DSC、转矩流变仪、表面轮廓仪等测试和表征了玉米淀粉/PCL复合片材的结构性能。结果表明,玉米淀粉/PCL复合片材表面微观形貌光滑,各组分共混均匀,具有一定相容性。复合片材熔体在常规塑料加工温度区间内流动性良好,显示其优良的加工性能。复合片材的力学性能和使用性能达到国家标准(GB/T4455—94)要求。     

硅烷偶联剂处理对连续玄武岩纤维帘线/橡胶界面性能的影响

采用硅烷偶联剂KH 550处理连续玄武岩纤维(CBF)帘线,并与天然橡胶(NR)/丁苯橡胶(SBR)基质制备H型试样,研究了KH 550浓度对CBF帘线力学性能及CBF帘线与橡胶基质间的静态黏合性能和疲劳性能的影响,追踪了CBF帘线与橡胶基质间的疲劳破坏演变过程。结果表明,KH 550的处理可以在一定程度上改善CBF帘线的力学性能以及与橡胶基质的黏合性能,并可显著提高CBF帘线/橡胶界面的疲劳寿命。KH 550最佳质量分数为0.75%时,CBF/橡胶界面的疲劳寿命可提高100%。     

低压片状模塑料模压参数及其性能研究

研究了模压工艺参数、模压流动中纤维取向等对LPMC力学性能、表面质量的影响.结果表明,当模压温度115℃、LPMC片材放入模具后15 s加压、最后25 mm行程时间为15 s、保压时间6 min的条件下,片材具有最佳的力学性能和表面质量.制品弯曲强度几乎不受取样位置的影响,但试样在纤维取向(纵向)比垂直方向(横向)具有更高的强度和模量.     

复合拉伸力场挤出HDPE片材的力学性能

利用收敛-发散口模挤出制备了高密度聚乙烯(HDPE)片材,研究了挤出温度对片材力学性能的影响.结果表明:在复合拉伸力场作用下,熔态挤出(140℃)片材的纵、横向屈服拉伸强度分别为28.3,27.0MPa,固态挤出(112℃)片材的纵、横向屈服拉伸强度分别为181.4,51.3 MPa,纵、横向屈服拉伸强度分别增加了540%和90%.与固态挤出相比,熔态挤出片材纵、横向断裂伸长率分别增加了760%和124%.扫描电子显微镜显示,熔态挤出HDPE片材由球晶结构构成;固态挤出片材由大量垂直于挤出方向规整排列的片晶组成,并有少量的串晶生成,片晶厚度增加,这种结构有利于改善制品的双向力学性能.     

特种酚醛树脂基烧蚀复合材料的研究

对T-700碳纤维(T-700CF)、特种玻璃纤维(HSGF)、S-2高强玻璃纤维(S-2GF)、连续玄武岩纤维(CBF)的基本力学性能和热性能进行了研究和对比,同时对T-700CF、HSGF、S-2GF、CBF增强特种酚醛树脂1(PR1)复合材料的力学性能和烧蚀性能进行了对比,探讨了PR1/CBF的烧蚀机理。结果表明,PR1/T-700CF的弯曲性能和烧蚀性能最佳;PR1/CBF次之,能够取代PR1/S-2GF和PR1/HSGF;PR1/CBF的氧-乙炔烧蚀过程中主要存在着材料吸热、基体材料与气流的热化学反应、热辐射效应、增强材料的熔化和升华、高速粒子和气流冲刷、机械剥离等烧蚀机理。     

我国抗震补强芳纶片材面世

承担国家863计划项目的杭州索奇先进复合材料有限公司，继创新研制出加固用高性能碳纤维片材后，又与日本帝人合作，首选其高模型芳纶，成功研发出适用于抗震补强的高性能芳纶片材。经国家法定检验机构对该芳纶片材多批次小样检测结果表明，其力学性能在全球同类产品中首屈一指(详见参比表)。     

PF/玄武岩纤维/CNTs复合材料的研究

利用碳纳米管(CNTs)对酚醛树脂(PF)/玄武岩纤维(CBF)复合材料进行改性.研究了CNTs含量对PF/CBF复合材料力学性能和烧蚀性能的影响.研究表明,CNTs的加入能明显提高复合材料的力学性能,当CNTs质量分数为1.5％时,复合材料的弯曲强度最大,较未加入CNTs的复合材料提高约39.5％;当CNTs质量分数...     

聚乙烯在复合应力场中临界状态挤出成型的研究

采用具有复合应力场的双向拉伸挤出口模，在临界状态下成功制备了聚乙烯双向自增强片材。研究表明，制备的增强片材的纵横向力学性能均有明显提高，维卡软化点提高了21℃。微观测试表明，其晶态结构为串晶，正是由于片材内部生成了大量的串晶结构，才赋予了增强片材比较好的力学性能。     

长玻纤增强ASA/PVC夹芯复合板材的制备及性能

采用在线混配法制备了长玻纤增强ASA复合片材和夹芯复合板材。通过实验制备了不同玻纤含量长玻纤复合片材时,双螺杆挤出机的主机转速、喂料转速及纤维束数。研究了制备工艺对片材性能的影响,采用微观电镜分析了接枝料及玻纤含量对片材力学性能的影响,并通过残余玻纤长度的测量分析了片材力学性能与玻纤长度之间的关系。通过工艺优化,将长玻纤增强ASA片材热覆于PVC发泡板的表面,快速冷压成型,制备了长玻纤增强ASA/PVC夹芯复合板材,得到了不同面层对复合板材弯曲、冲击等力学性能的影响。结果表明,当长玻纤含量为20%时,制备的夹芯复合板材的性能最佳,其弯曲强度、弯曲模量均达到Ⅱ类强度实芯建筑模板用木塑复合板的标准。     

不饱和聚酯片状模塑料力学性能的研究

研究了玻纤布、短切玻纤及碳酸钙对不饱和聚酯片状模塑料力学性能的影响,实验发现:玻纤布增强不饱和聚酯片状模塑料的力学性能比短切玻纤好,随着玻纤含量的增加,不饱和聚酯片状模塑料的拉伸强度先增加,达到一极大值之后减少。碳酸钙填充不饱和聚酯片状模塑料,随着碳酸钙含量的增加,不饱和聚酯片状模塑料的拉伸强度明显降低,弯曲强度增加。     

骨组织工程中的碳纤维材料

归纳了聚合物支架材料在提高其力学性能方面的一些研究工作,并综述了碳纤维材料在骨组织工程上应用的进展.分析表明,骨组织工程是修复骨缺损的有效方法之一,而碳纤维材料的结构性能优势使其成为提高组织工程支架性能的首选材料之一.在提高聚合物支架力学性能的同时,进一步提高材料的生物活性和促进骨的修复是目前研究的重点和难点.指出可通过对碳纤维材料的改性、有序排列等手段来进一步提高碳纤维材料的作用.     

Mechanical properties of ultrahigh-molecular-weight polyethylene fiber-reinforced PE composites

Three types of high-strength polyethylene (PE) fiber-reinforced composite sheets were made by compression molding at the vicinity of melting point of the fiber. Sheet I was molded from only PE fibers. Sheets II and III were prepared by the compression molding of PE fiber with conventional high- and low-density polyethylene films, respectively. The mechanical properties, thermal behavior, and morphologies of the sheets have been investigated and compared with each other. The tensile strength and elastic modulus of sheet III are 660 MPa and 14 GPa, respectively, which were 60 and 30 times higher than those of typical low-density PE film. Although the elastic modulus of sheet III is 6 GPa less than that of sheet II, the tensile strength of 660 MPa is highest in the three types of sheets prepared in this study. The mechanical properties of sheets II and III were about half of predicted theoretical ones. It was concluded that the interfacial adhesion between PE fiber and PE matrix was an important factor to improve the mechanical properties of this PE sheet. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 1431–1439, 1998     

加固用复合材料力学性能的影响因素

在土木工程中，混凝土结构的加固补强要求连续纤维增强树脂基复合材料应具有较高的抗拉强度、弹性模量和一定的断裂延伸率，本文探讨了在一定成型工艺和环氧树脂基体的条件下，影响这些性能的因素．试验表明，纤维品种、纤维表面处理方法、片材厚度对这些性能有显著的影响；纤维束或纤维布与树脂基体复合固化后，由于固化应力的作用，其增强效率将大大下降。对此，在加固设计时应予以重视。     

Applications of a fiber orientation prediction algorithm for compression molded parts with multiple charges

An application of a finite element simulation of mold filling and predication of fiber orientation in fiber filled compression molded parts is presented. Three-dimensional thin-walled geometries are considered. Following a simulation of the filling process, a set of transort equations are solved to predict the locally planar orientation of short fiber composites. The final orientation states throughout the part provide the necessary information to obtain a locally orthotropic mechanical model of the composite. A sheet molding compound part with a multiple charge pattern is used to illustrate the generality of the algorithms developed for compression flow, fiber orientation, and property predications. Derivations of the orthotropic mechanical properties obtained from the fiber orientation results are outlined.     

Influence of Coir Fiber Geometry on Mechanical Properties of SiC Filled Epoxy Composites

Silicon - The objective of this study is to attempt the possibility to employ eco-friendly fiber in composite material for engineering applications. Also, evaluate its mechanical properties like...     

Effects of coupling agents on the properties of an NR/SBR matrix and its adhesion to continuous basalt fiber cords

The effects of various coupling agents on the characteristics and properties of a natural rubber (NR)/styrene–butadiene rubber (SBR) matrix and its adhesion to continuous basalt fiber (CBF) cords were studied. Four types of silane-based and two types of titanate-based coupling agents were added separately to the rubber matrix during the mixing process. The processability of the rubber compounds and the mechanical and tension fatigue properties of the vulcanizates were evaluated. The static and dynamic adhesion between the CBF cord/rubber matrices were investigated using the H pull-out test and an elastomer testing system, respectively. The results showed that the effects of the coupling agent were controlled by its chemical structure, and it was found that the addition of (3-aminopropyl)triethoxysilane was the most effective for enhancing the interfacial fatigue properties, due to the combined improvements of the initial adhesion, interfacial stress states, and the fatigue property of the rubber matrix. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47098.     

The effect of water‐soluble polymers on rheology of microfibrillar cellulose suspension and dynamic mechanical properties of paper sheet

Rheological properties of fiber/polymer suspensions and dynamic mechanical analysis (DMA) of paper sheets containing the same polymers were measured. Correlations between viscoelastic properties of suspensions and strength of paper sheet are presented. Rheological properties of suspensions of microfibrillar cellulose (MFC) and a set of water soluble polymers were measured. Rheological properties of these complex fluids vary considerably depending on the added polymer. A suspension of fiber and carboxymethyl cellulose (CMC) exhibits a viscosity higher than the sum of the viscosity of the individual components in the suspension. In contrast, when cationic starch (CS) is used together with the fiber, the yielding behavior rather than the viscosity is characteristic of the suspension. Dynamic mechanical properties of paper sheets containing CMC or CS as additives were studied at different humidity levels. Different yielding behavior observed in oscillatory rheology can be correlated with straining behavior in dynamic mechanical properties. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

丙纶纤维自增强聚丙烯树脂的研究

以丙纶纤维为增强体,聚丙烯树脂为基体,采用热压成型的方法制备丙纶纤维/PP复合材料板材.研究了不同热压温度、不同纤度的丙纶纤维用量对复合材料力学性能的影响.结果表明:本实验最佳热压温度为195℃,在此温度下,随着纤维用量的增加,复合材料的拉伸强度呈先升后降的趋势,在用量为15%时达到最高点,纤度为240D的丙纶纤维/P...