电线电缆用聚氯乙烯复合材料的阻燃性能和力学性能研究

为提高电线电缆用聚氯乙烯（PVC）的阻燃性能，向PVC中加入硼酸锌（ZB）制备了PVC复合材料，并研究其阻燃性能和力学性能。力学性能测试表明：随着ZB掺量的增加，PVC复合材料的拉伸性能逐渐降低，但是ZB掺量不超过6%时，PVC复合材料的拉伸性能降低幅度不大，仍满足相关标准要求。阻燃性能测试表明：随着ZB掺量的增加，PVC复合材料的阻燃性能不断提高。当ZB掺量为6%时，PVC复合材料（4#）的综合性能优异，与未加ZB相比，4#试样的阻燃性能提高明显，氧指数达到40.1%，垂直燃烧等级达到FV-0级，烟密度降为72,HCl释放量降为41 mg/g，热释放速率峰值（PHRR）降低17.4%，总热释放量（THR）降低36.5%,600 s内的总产烟量（TSP600 s）降低69.7%；复合材料的拉伸强度下降10.8%，断裂伸长率下降12.7%。     

木质纤维对木塑复合材料力学性能和吸水性能的影响

以稻壳粉、竹粉为增强体,以非医疗回收塑料为基体,制备了粉体/非医疗回收塑料木塑复合材料,研究了粉体粒径、用量及种类对木塑复合材料力学性能和吸水性能的影响,用扫描电子显微镜对复合材料断面进行观察。结果表明:稻壳粉/非医疗回收塑料木塑复合材料的力学性能随稻壳粉粒径的增大先上升后下降,吸水率随着稻壳粉粒径和用量的增加分别呈下降和上升趋势;当稻壳粉用量为50%、粒径为40目时,稻壳粉/非医疗回收塑料木塑复合材料的综合力学性能最佳,其拉伸强度、拉伸模量、弯曲强度、弯曲模量比纯非医疗回收塑料分别提高8.68%、164.99%、47.72%、184.83%。竹粉/非医疗回收塑料木塑复合材料的力学性能要优于稻壳粉/非医疗回收塑料木塑复合材料,其拉伸强度、拉伸模量、弯曲强度、弯曲模量比稻壳粉/非医疗回收塑料木塑复合材料分别提高5.16%、19.63%、12.88%、18.51%,比纯非医疗回收塑料分别提高14.28%、217.01%、66.75%、237.56%。     

稻壳/PP-LDPE微孔发泡木塑复合材料

考察AC发泡剂用量及稻壳粉用量对复合材料密度、力学性能及微观结构的影响,结果表明:随着AC发泡剂用量的增加,复合材料的密度降低,冲击强度先增加后降低,拉伸强度急剧降低;发泡剂用量为2.5份时,密度最低为0.90 g/cm~3,冲击强度最高为6.4 kJ/m~2.稻壳粉的加入,增加了材料的密度,降低了冲击强度和拉伸强度.综合考虑,AC发泡剂用量为2.5份,稻壳粉用量为30份,复合材料的性能较好.     

木粉对PVC发泡木塑复合材料性能的影响

采用PVC树脂和木粉加入发泡剂制得PVC/木粉发泡复合材料。本文对木粉进行了热重分析,考察木粉粒径及含量对PVC/木塑发泡材料性能的影响,考察了木粉含量对发泡、熔融指数、转矩加工流变性以及耐候性的影响。结果表明:TG分析表明PVC/木塑复合材料加工的最佳温度200℃左右。随着木粉粒径的减小,PVC/木粉复合材料的冲击强度和弯曲强度出现先上升后下降的趋势,100目木粉,力学性能最好。随着木粉用量的增加,体系的拉伸强度、冲击强度和弯曲强度均呈降低的趋势,材料的发泡效果变差,流动性、稳定性、耐候性变差,因此PVC木塑复合材料应该控制其木粉含量。     

氢氧化镁表面有机化及在阻燃PVC中的应用

采用原位聚合的方法在氢氧化镁[Mg(OH)2]表面接枝聚合聚甲基丙烯酸甲酯(PMMA)。考察了PMMA包覆量对Mg(OH)2粉体的吸油值、水中的沉降速度、水接触角以及对阻燃PVC复合材料中的氧指数(LOI)、形貌结构及力学性能的影响。结果表明,随着PMMA包覆量的增加,粉体的吸油值及粉体在水中的沉降速度明显减小,水接触角明显变大。在PVC复合材料中的氧指数减小,但变化不大。形貌结构分析表明,PMMA经处理后粉体与PVC基体的相容性明显提高,力学性能由于粉体的加入量随着PMMA包覆量的增加而增多,导致拉伸强度和撕裂强度逐渐降低,断裂伸长率先增大后减小。     

聚丙烯竹塑复合材料的研究

研究了竹粉粒径以及两种不同的偶联剂对聚丙烯基竹塑复合材料力学性能的影响,比较分析了偶联剂种类和用量对复合材料力学性能的改善效果.结果表明,不同颗粒大小的竹粉对竹塑复合材料力学性能影响不大,而偶联剂对其拉伸、弯曲和冲击强度的影响差别较大,其中以冲击强度的增加最大.     

竹粉/PVC发泡复合材料的制备与性能研究

采用模压法制备了竹粉/聚氯乙烯(PVC)发泡复合材料,研究了邻苯二甲酸二辛酯(DOP)、发泡剂偶氮二甲酰胺(AC)、竹粉、成核剂及成型压力对复合材料密度和力学性能的影响。结果表明:添加DOP使复合材料密度和拉伸强度下降,断裂伸长率快速增大;AC发泡剂用量增加,复合材料密度减小;竹粉用量增加,复合材料密度增加,力学性能变差;纳米二氧化钛和轻质碳酸钙的添加能有效改善复合材料的性能,其最佳用量为2份;复合材料最佳成型压力为6 MPa。     

PCL／CaSO4复合材料的力学性能研究

采用不同粒度的CaSO4与聚己内酯（PCL）熔融共混，并对复合后的材料进行了力学性能研究。研究表明，复合材料的拉伸强度及断裂伸长率随着CaSO4的含量的增多而降低。偶联剂的种类和用量对复合材料的力学性能都有影响，其中用硅烷类偶联剂JH-0187处理过的效果最好，最佳用量为2％，此时拉伸强度和断裂伸长率分别为25MPa和750％。此外，CaSO4的粒径对复合材料的力学性能也有影响，粒径越小复合材料的拉伸强度和断裂伸长率越好。     

玻璃微珠改性PP和LLDPE力学性能的比较研究

采用玻璃微珠(GB)改性聚丙烯(PP)和线性低密度聚乙烯(LLDPE)，对玻璃微珠的用量、粒径和复合材料加工方法对材料的力学性能的影响进行了比较研究。结果表明：随着GB用量的增加，单、双螺杆挤出GB／PP复合材料的拉伸模量、弯曲强度和弯曲模量均呈线性增长的趋势，而屈服强度则有小幅下降；断裂应变在低含量时有所提高，然后迅速下降；单双螺杆挤出材料的冲击强度均有所提高，并在一定范围内随GB用量的提高而增大，且单螺杆挤出材料的冲击强度略高于双螺杆挤出材料。而GB／LLDPE中，随着GB用量的增加，单螺杆挤出复合材料的拉伸模量、弯曲模量均呈线性增长趋势，而屈服强度和弯曲强度在含量较高时略有上升；双螺杆挤出复合材料的拉伸模量、屈服应力、弯曲强度和弯曲模量均呈线性增长的趋势，两者的断裂应变都有所降低，但没有严重劣化LLDPE复合材料的冲击特性。GB的粒径对两种复合材料的力学性能影响不大，但对GB／PP复合材料的韧性有较大影响。单、双螺杆挤出GB／PP复合材料的冲击强度在一定范围内较纯料有一定提高；同样的，双螺杆挤出复合材料的冲击强度低于单螺杆挤出材料。     

PVC/HGB拉伸性能的研究

应用Instron材料试验机在室温下测量了空心玻璃微珠（HGB）填充聚氯乙烯（PVC）复合材料（PVC／HGB）拉伸性能。结果表明：试样的弹性模量随着HGB体积分数（φf)的增加而线性增大；而屈服拉伸强度（σyc)和拉伸断裂能则随着φf的增加而缓慢下降，当φf为5％－20％时，PVC／HGB的断裂拉伸强度（σbc)均高于未填充PVC；HGB粒径对试样的σyc和σbc的影响不太明显。当φf为5％时，PVC／HGB的拉伸强度均高于PVC/CaCO3复合材料。     

聚丙烯/鳞片石墨导热复合材料的制备及性能

以聚丙烯(PP)为基体,鳞片石墨(FG)为填料,通过添加偶联剂、开炼机混炼、模压成型的方法,制备了具有较高热导率和优良力学性能的PP/FG导热复合材料。考察了硅烷偶联剂的品种及用量、FG的粒径及含量对复合材料热导率和力学性能的影响。结果显示,使用偶联剂处理的FG对复合材料的力学性能具有一定的增强作用,但是材料的热导率降低;当KH 550添加量为FG含量的1%时,材料的力学性能最好;随着FG粒径的增大,材料的热导率明显提高,力学性能相应下降,粒径为17μm的FG与148μm的FG制备的复合材料相比,热导率提高了52.3%,拉伸强度和弯曲强度分别由34.4 MPa和51.5 MPa下降到25.1 MPa和43.0 MPa;随着FG含量的增加,材料的热导率增大,当17μm的FG含量为70%时,材料的热导率是纯PP的22.1倍,拉伸弹性模量和弯曲弹性模量也随之增大,断裂拉伸应变和断裂弯曲应变减小,拉伸强度和弯曲强度先减小后增大,并且在FG含量为20%时降到最低。     

Role of paper sludge particle size and extrusion temperature on performance of paper sludge–thermoplastic polymer composites

The effect of paper sludge's particle size and extrusion temperature on the physical and mechanical properties of paper sludge–thermoplastic polymer composites was investigated. In the experiment three levels of particle sizes for the paper sludge and four extrusion temperatures were designed to examine the physical and mechanical properties of these composites. The ash contents of the paper sludge were about 73.7, 46.2, and 38.1% with particle sizes of below 0.15, 0.18–0.25, and 0.42–0.84 mm, respectively, which meant lower ash content and higher cellulose fiber content, in the larger particle size of paper sludge. As the particle size of the paper sludge decreased, the swelling thickness, water absorption, and tensile and flexural strengths of the composite improved; but the particle size of the paper sludge had no effect on its unnotched impact strength. With the increase of the extrusion temperature the thickness swelling and water absorption of the composites were slightly improved but not statistically different. A rise of the extrusion temperature generally had a positive effect on the tensile and flexural properties of the composite. The notched and unnotched impact strengths of the composite increased with the increase of the extrusion temperature from 190 to 230°C, but they decreased slightly at an extrusion temperature of 250°C. This low impact energy at an extrusion temperature of 250°C may be attributed to the excessively brittle fibers from thermal decomposition. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2709–2718, 2001     

Effect of tensile rates on thermal and mechanical properties of porous PTFE composites

To achieve polymer-matrix composites for sealing materials with thermostability and toughness, PTFE composites filled with short glass fibers (SGFs) were hyperthermal stretched to prepare a substrate material with high thermal stability and porosity. The effects of various tensile rates on the thermal and mechanical properties and morphologies were investigated. The results revealed that the thermal stability could be improved slightly and the thermal expansion coefficient of composites increased by the tensile rate. Through observing the morphologies, tensile process produced cavities and the increased tensile rate had negligible effects on porosity, which also could be proved by density test. From mechanical properties analysis, stretched composites exhibited that the tensile strength increases first and then decreases with the increased tensile rate. Although the variation tendency of Young's modulus is similar to that of tensile strength, which is smaller than that of unstretched composite. When the tensile rate reached 50 mm·min⁻¹, the tensile strength and Young's modulus of the stretched composites increased by 65 and 9% to maximum, respectively. Meanwhile, elongation at break and shore hardness decreased. The thermal and mechanical properties improvement could be ascribed to the strain-induced crystallization and crystal alignment. In addition, the interplanar spacing and grain size were inversely proportional to the tensile rate. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48175.     

PP/甘蔗皮纤维复合材料的拉伸性能

采用热压工艺制造聚丙烯(PP)/甘蔗皮纤维复合材料,并研究其拉伸性能。研究热压温度为175℃、压力为2 MPa、时间15 min工艺条件下纤维粒径大小和质量分数对复合材料拉伸强度和拉伸弹性模量的影响。结果表明:在甘蔗皮纤维质量分数为40%条件下,复合材料拉伸性能随着粒径减小呈现先增加后减少的趋势,当纤维粒径为40~60目(0.45~0.3 mm)时材料拉伸强度最大,为8.58 MPa,此时弹性模量为2.44 GPa;在相同纤维粒径40~60目条件下,纤维质量分数为40%时PP复合材料拉伸强度最大,纤维质量分数为50%时PP复合材料拉伸弹性模量最大,达到2.65 GPa。根据实验结果,甘蔗皮纤维增强PP复合材料在纤维粒径为40~60目、质量分数在40%时综合拉伸性能最佳。     

PVC/WF复合发泡材料的研究

采用一步模压法制备聚氯乙烯/木粉(PVC/WF)复合发泡材料,研究木粉(WF)的预处理、用量及粒径对PVC/WF复合发泡材料力学性能、尺寸稳定性、密度、吸水性及吸油性能的影响,并通过扫描电镜(SEM)对其泡孔结构进行分析.结果表明:WF经预处理,PVC/WF复合发泡材料拉伸强度有所增强,密度和吸水率略有减小,吸油性尤明显变化,耐热性稍有降低;随着WF粒径的增加,PVC/WF复合发泡材料的密度、吸水率、吸油率和线性收缩率均增大,拉伸强度从1.25MPa增大到1.78 MPa,断裂伸长率随之减小;随着WF含量增加,PVC/WF复合发泡材料密度和吸油率均明显增加,拉伸强度也随之增大,线性收缩率减小,吸水率先增大后减小,WF质量分数10%时吸水率最大.     

木粉填充聚乙烯复合材料的研究

研究了线型低密度聚乙烯（ＬＬＤＰＥ）／木粉复合材料的力学性能及生方法。结果表明，随木粉含量的增加，ＬＬＤＰＥ／木粉复合材料的冲击强度和拉伸强度均下降。用过氧化二异丙苯（ＤＣＰ）引发聚乙烯交联能显著提高复合材料的力学性能。用表面活性剂对木粉进行预处理后，在改善复合材料加工性能的同时，使复合材料的冲击强度略有提高，但拉伸强度下降。不饱和聚酯与ＤＣＰ并用有良好的协同性。     

PP/硅藻土复合材料拉伸性能的研究

考察了硅藻土粒径和含量对填充聚丙烯复合材料的拉伸性能的影响。结果表明,当硅藻土体积分数时,复合材料的拉伸强度和断裂强度都有所下降,然后,两者均有轻微的提高;除个别测量点外,复合材料的断裂伸长率随着的增加而明显增大;当时,硅藻土粒径为7μm的填充体系的拉伸强度和拉伸断裂强度最高。     

Effect of filler content and size on the properties of ethylene vinyl acetate copolymer–wood fiber composites

In this study, the main focus was on the effect of wood fiber (WF) content and particle size on the morphology and mechanical, thermal, and water‐absorption properties of uncompatibilized and ethylene glycidyl methacrylate copolymer (EGMA) compatibilized ethylene vinyl acetate copolymer–WF composites. For uncompatibilized composites, the tensile strength decreased with increasing WF content, whereas for compatibilized composites, the tensile strength initially decreased, but it increased for composites containing more than 5% WF. Small‐WF‐particle‐containing composites had higher tensile strengths than composites containing larger WF particles, both in the presence and absence of EGMA. WF particle size did not seem to have much influence on the degradation behavior of the composites, whereas water absorption by the composites seemed to be higher in composites with smaller particle sizes for both compatibilized and uncompatibilized composites. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3645–3654, 2007     

Characterization of copper–silicon nitride composite electrocoatings

Silicon nitride particles were incorporated to electrolytic copper by co-electrodeposition in acidic sulfate bath, aiming the improvement of its mechanical resistance. Smooth deposits containing well-distributed silicon nitride particles were obtained. The current density did not show significant influence on incorporated particle volume fraction, whereas the variation of particle concentration in the bath had a more pronounced effect. The microhardness of the composite layers was higher than that of pure copper deposits obtained under the same conditions and increased with the increase of incorporated particle volume fraction. The microhardness of composites also increased with the increase of current density due to copper matrix grain refining. The composite coatings were slightly more corrosion resistant than pure copper deposits in 3.5% NaCl solutions.