PP/SBS/滑石粉三元复合材料性能研究

通过熔融共混制备了不同滑石粉(经偶联剂KH550表面改性)用量的聚丙烯(PP)/丁苯热塑性弹性体(SBS)/滑石粉复合材料(PP与SBS的配比固定为90/10),同时研究了该复合材料的力学性能和流动性能。结果表明:随着滑石粉用量的增加,PP/SBS/滑石粉复合材料的弹性模量和拉伸强度下降;弯曲性能、冲击性能和熔体流动速率则先提高后降低,且均在滑石粉用量为10份时达到最大值;另外添加了改性滑石粉的PP/SBS/滑石粉复合材料,其拉伸强度、冲击强度和熔体流动速率均高于未改性滑石粉填充的复合材料。     

改性勃姆石对聚丙烯性能影响研究

将勃姆石用酞酸酯偶联剂（TC-114）进行活化改性处理,将其与聚丙烯（PP）进行熔融挤出得到PP/改性勃姆石复合材料,采用热重分析仪、差示扫描量热仪、极限氧指数测试仪、锥形量热仪等探究改性后勃姆石对PP性能的影响。结果表明,经过偶联剂处理的勃姆石填充PP后所得的复合材料的弯曲强度与纯PP对比的提高了14.4 %,冲击强度提升了30.6 %,而与未改性勃姆石填充的复合材料比弯曲强度提高了6.9 %,冲击强度提升了5.7 %,且断裂伸长率相较于未改性的复合材料提升4倍;改性勃姆石填充聚丙烯复合材料的熔体流动速率、热稳定性以及极限氧指数相较于纯PP都有较大程度提升;改性后的勃姆石有增强聚丙烯力学性能性能的效果,并且随着填入量的增加,热稳定性和阻燃性能都随之提高。     

原位聚合改性氢氧化镁在EVA中的应用

通过苯乙烯在氢氧化镁颗粒表面的原位聚合，由化学改性法提高了颗粒表面的憎水性和亲油性，DSC和熔体流动速率等测定结果表明：经化学改性提高了氢氧化镁样品的热分解温度，使其吸水性明显下降，在乙烯一醋酸乙烯酯共聚物(EVA)基体树脂中的分散性得到改善；SEM观察发现采用原位聚合改性后的氢氧化镁与EVA基体树脂的相容性明显优于未改性氢氧化镁。将其填充EVA，明显改善了材料的力学性能和加工性能，材料的断裂伸长率提高4倍以上。     

PBMA原位包覆硅灰石填充改性聚丙烯的研究

采用不同的方法处理硅灰石填充改性PP,研究了经不同处理工艺处理的硅灰石对PP复合材料力学性能及加工流动性的影响。结果表明:在相同用量下,经PBMA表面包覆方法处理的复合材料比偶联剂JN-101处理的屈服强度要高,同时经过表面包覆的硅灰石能使PP屈服强度提高45.9%。SEM分析表明:经表面包覆的硅灰石分散能力大幅度提高,与基体界面结合较好;复合材料的熔体流动速率随着包覆硅灰石添加量的增加而降低。     

玻璃微珠改性PP和PE-LLD的加工流变行为

采用玻璃微珠改性两种基体性质显著不同的聚烯烃并对玻璃微珠的含量、粒径和复合材料加工方法对材料的加工流变行为进行了研究。结果表明：加工方法、玻璃微珠含量和粒径对聚丙烯/空心玻璃微珠(PP/GB)复合材料的熔体流动速率和转矩流变性能的影响远大于对PE-LLD/GB复合材料的影响，其中玻璃微珠含量的影响较粒径大。研究认为，无机刚性粒子填充改性热塑性聚合物时，加工方法、填料含量、几何特征等对复合材料流变特性是否发生影响，影响的程度等，更重要的是取决于基体树脂的特性。     

矿物填充改性聚丙烯熔接痕强度研究

研究了聚丙烯(PP)基体的熔体质量流动速率、矿物填充剂填充量、矿物填充剂类型等因素对填充改性聚丙烯复合材料熔接痕强度的影响。结果表明,矿物填充剂的形态结构和填充量是影响矿物填充改性聚丙烯复合材料熔接痕强度的关键因数。颗粒状矿物填充PP复合材料的熔接痕强度保持率最好,片层结构的矿物填充剂会显著降低矿物填充PP复合材料的熔接痕强度。     

PP/PET/MFIAA/HET原位成纤复合材料的力学性能与熔体流动性

研究了聚对苯二甲酸乙二醇酯（PET）含量、基体性质、成型加工温度对橡纤混杂型PP/PET/多功能界面活化剂（MFIAA）/高效增韧剂（HET）原位成纤复合材料力学性能和熔体流动性的影响。结果表明,MFC、HET用量不变,PET含量增大,微纤的数量增加,长径比增大,复合材料的刚性提高,韧性有所降低;基体PP的熔体流动速率增大,有利于PET微纤在制品中的保持,基体熔体流动速率为16.2 g/10min时,复合材料的缺口冲击强度、拉伸强度和弯曲模量分别达到原料PP的3.49倍、99 %和1.73倍,韧性显著提高的同时刚性保持率也很高;受熔体流动性和分散相形态的双重控制,PP/PET/MFIAA/HET较为适宜的成型加工温度为（200±10） ℃。PET微纤是造成PP/PET/MFIAA/HET流动阻抗增加的主要原因,随着PET含量的增大,复合材料的熔体流动性急剧降低。     

PP/SEBS/MH复合材料的制备及其性能研究

采用极限氧指数（LOI）和热重分析（TGA）研究了聚丙烯（PP）/氢化苯乙烯-丁二烯-苯乙烯嵌段共聚物（SEBS）/氢氧化镁（MH）复合材料的阻燃性能和热降解行为;探讨了SEBS和MH分别对PP/SEBS共混体系和PP/SEBS/MH复合材料力学性能和熔体流动速率的影响。结果表明：PP/SEBS/MH复合材料的力学性能和加工流动性能随着MH的质量分数增加而降低;复合材料高温下的热稳定性得到提高,MH分解吸热降低材料的热降解速率;MH以吸热方式在凝缩相和气相中发挥阻燃作用,复合材料阻燃性能得到提高,当MH的质量分数为60%时,LOI可达26.3%。     

HIPS／改性氢氧化镁晶须复合材料的研究

采用乙烯基硅烷在氢氧化镁(MH)晶须表面引入乙烯基后与苯乙烯进行原位聚合,得到了聚苯乙烯改性的氢氧化镁晶须(MMH).将MMH与高抗冲聚苯乙烯(HIPS)熔融复合制备了HIPS/MMH复合材料,研究了复合材料的微观结构和力学性能.结果表明,聚苯乙烯包覆在MH表面,并形成了共价键结合;原位聚合改性改善了MH在HIPS基体中的分散性,增强了MH和HIPS的界面相互作用,显著提高了HIPS/MMH复合材料的拉伸强度与冲击韧性.     

PP/LLDPE/芦苇木塑复合材料的制备与研究

以聚丙烯(PP)、线性低密度聚乙烯(LLDPE)制备了PP/LLDPE/芦苇木塑复合材料。研究了PP/LLDPE质量比以及芦苇用量对木塑复合材料性能的影响,并探讨了芦苇经硅烷偶联剂KH550,A-151、钛酸酯偶联剂NDZ-101改性后对木塑复合材料力学性能、加工流动性能、微观结构及热性能的影响。结果表明:当PP/LLDPE质量比为60/40,加入30份A-151改性芦苇时,木塑复合材料的综合性能最佳。与加入未改性芦苇的复合材料相比,拉伸强度、弯曲强度、冲击强度,分别提高了33.93%,23.59%,42.58%;熔体流动速率值提高了18.69%;扫描电镜分析显示,改性芦苇与PP,LLDPE的相容性较好。     

纳米SiO2粒子对PP结晶行为的影响

通过X-射线光电子能谱（XPS）对经偶联剂处理的纳米SiO2粒子（简称烷基化SiO2纳米粒子）和聚甲基丙烯酸甲酯（PMMA）接枝包覆SiO2纳米粒子（简称SiO2-g-PMMA复合纳米粒子）的表面组成进行分析。将纳米SiO2粒子，烷基化SiO2纳米粒子，复合纳米粒子分别与基体PP复合制备复合材料，通过DSC，WAXD和TEM等测试方法详细研究了PP/SiO2复合材料的结晶行为与力学性能，结果发现：纳米SiO2粒子与烷基化SiO2纳米粒子并不改变基体PP的结晶形态，而复合纳米粒子诱发了基体PP的β晶型结晶，复合纳米粒子比较均匀地分散于PP基体中，对复合材料的力学性能有较大的改善。     

凹凸棒土/聚合物复合材料研究进展

综述了凹凸棒土在聚合物中的应用研究进展。研究表明，大多数情况下，常规的聚合物加工技术不足以将凹凸棒土解离为纳米短纤维，因此只能形成凹凸棒土／聚合物微米复合材料，但将凹凸棒土进行有机改性，可以明显提高其增强效果。采用原位聚合的方法可以制备出性能优异的凹凸棒土／聚合物纳米复合材料，或在高黏度和高极性的聚合物熔体中，凹凸棒土在剪切力下可以解离为纳米单晶，从而形成纳米复合材料。利用凹凸棒土／乳液共混共凝方式也可制备出凹凸棒土／橡胶纳米复合材料。     

Structure and properties of polypropylene composites filled with magnesium hydroxide

Silane and silicone oil modified superfine magnesium hydroxide (MH) was filled into polypropylene (PP) as a flame retardant. The PP and flame‐retarded PP composites were studied for their mechanical properties and rheological behaviors by differential scanning calorimetry (DSC), polarizing optical microscopy (POM), limiting oxygen index (LOI), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The results showed that the addition of MH improved flame retardancy of PP/MH composites, but seriously deteriorated mechanical properties of the composites. Surface treatment of MH could significantly improve tensile and impact strength of PP/MH composite because of its enhanced interfacial adhesion between MH and PP matrix. DSC results showed that MH had heterogeneous nucleation effect on PP. Surface treatment of MH weakened its heterogeneous nucleation effect. POM results showed that the dispersion of MH particles played an important role in the crystalline morphology and spherulite size of PP crystals. TGA indicated that MH greatly enhanced the thermal stability of PP. The introduction of treatment agent further improved the thermal oxidative stability of the composite. According to LOI, silane‐treated MH greatly enhanced flame retardancy of PP/MH composites. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4943–4951, 2006     

Crystallization behaviors and foaming properties of diatomite-filled polypropylene composites

The non-isothermal crystallization kinetics and foaming properties of polypropylene (PP) filled with various contents of diatomite were investigated. The results showed that the diatomite had strong effects on the PP crystallization kinetics, which significantly increased the crystallization temperature and reduced crystallite size. These were attributed to the nucleation effect of the diatomite particles and the complex interface properties between the PP chains and diatomite particles. Non-isothermal crystallization can be well described by the Mo’s method. The non-isothermal crystallization activation energy calculated by the Kissinger’s method increased with increased content of diatomite. The foamed PP composites, in particular, the PP composites filled with 10 wt% diatomite had better cell morphology ascribed to the facilitated crystallization and increased polymer melt strength compared with the foamed pure PP.     

One-step synthesis of hydrophobic magnesium hydroxide nanoparticles and their application in flame-retardant polypropylene composites

Hydrophobic magnesium hydroxide (MH) nanoparticles were prepared by a one-step synthesis method in a high-gravity environment generated by a novel impinging stream-rotating packed bed (IS-RPB) reactor. The reactant solutions were simultaneously and continuously pumped into the IS-RPB reactor, and then Tween 80 was added as a surface modifier. The morphology, structure, and properties of blank and hydrophobic MH were characterized. The effects of MH nanoparticles on the flame retardancy, thermal stability, and mechanical properties of PP/MH composites were also studied. We found that the obtained MH nanoparticles exhibited hexagonal lamella with a mean size of 30 nm, excellent hydrophobic properties (e.g., high water contact angle of 112°), and improved thermal stability of MH. The limiting oxygen index (LOI) further showed that increased MH loading can significantly improve flame-retardant performance, which reached 29.3% for PP/MH composites with 30 wt% hydrophobic samples. The thermal stability and mechanical properties of the PP/MH composites with hydrophobic samples were also much higher than those of PP/MH composites with blank MH. Results showed that the one-step synthesis had high potential application in the large-scale production of hydrophobic MH nanoparticles.     

Polymer nanocomposite powders and melt spun fibers filled with silica nanoparticles

Nanocomposite powders from polypropylene filled with surface modified and unmodified fumed silica have been prepared from polymer solution to achieve improved mixing and have been forwarded to fiber melt spinning. The surface of the fumed silica was modified with dodecyl alkoxy silanes. Crystallization velocity and viscosity of the PP nanocomposites thereof were determined to ensure good melt spinning processing conditions for all composite compositions. Upon addition of untreated filler particles, a shear thinning and an increased crystallization velocity of the polymer melt was found, while only minor changes were detected in the presence of surface modified fumed silica particles. The composites and the polymer fibers made from these powder composites by melt spinning were mainly characterized by optical microscopy (OM), scanning electron microscopy (SEM), mechanical measurements, differential scanning calorimetry (DSC), and solid‐state NMR. The unmodified fumed silica was found to have a strong influence on the mechanical fiber properties, while the surface modified silica only a small one. Fibers were additionally characterized with respect to the uniformity, the PP crystallinity, moisture absorption, and the water contact angle. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 218–227, 2007     

Enhanced flame retardancy,smoke suppression,and acid resistance of polypropylene/magnesium hydroxide composite by expandable graphite and microencapsulated red phosphorus

Low flame retardant efficiency and poor acid resistance of filled polymer composites are two main drawbacks of magnesium hydroxide (MH) as a flame retardant (FR). To solve these problems, expandable graphite (EG) and microencapsulated red phosphorus (MRP) were introduced into polypropylene/magnesium hydroxide (PP/MH) composite by melt compounding. The obtained PP/MH/EG/MRP quadruple composite was studied regarding its fire behavior as well as acid resistance. Obvious flame retardant synergism among MH, EG, and MRP is found in PP, which diminishes the loading of FR from 63.0 to 37.5 wt% to obtain V-0 rating in UL-94 test and low smoke release. Compact intumescent char with high thermo-oxidative stability was generated on composite surface, which plays a vital role in flame retardancy. The removal of MH by acid erosion on PP/MH/EG/MRP composite surface does not affect production of intumescent char and fire behavior of this composite. The composite displays good fire retardancy, smoke inhibition, and acid resistivity concurrently. This article renders an easy and cheap route to overcome the main faults of MH.     

聚合物原位复合纳米碳酸钙增韧PP研究

通过有机单体原位聚合包覆的CaCO3与PP熔融混合制备了PP／CaCO3纳米复合材料，经过正交实验研究了填料饱覆聚合物比、接枝聚丙烯以及复合填料含量对PP缺口冲击强度的影响，结果表明：复合纳米CaCO3只需填加5％就可以将缺口冲击强度提高为原树脂的2倍左右。     

天然胶乳包覆交联聚苯乙烯刚性粒子改性聚丙烯的研究

将天然胶乳包覆到交联聚苯乙烯刚性粒子（N-XPS）上，探讨了N-XPS和包覆剂用量对N-XPS／PP复合材料性能的影响，结果表明：当包覆剂用量为XPS的20％，N—XPS用量为PP的3％时，复合材料的弯曲强度提高30％，简支梁与悬臂梁缺口冲击强度分别提高68％和88％。偏光显微镜观察到加入N-XPS的PP晶粒细化、界面模糊，这一事实证明了N—XPS粒子与PP有好的相容性和诱导结晶成核作用。转矩流变仪测试结果表明：随N—XPS用量的增加，复合材料加料熔融的最大扭矩及物料最低温度有明显的下降，物料达最低温度后，温度增长速率减慢，130s后，温度增长的速率呈上升趋势。     

纳米CaCO_3的接枝改性及其填充PVC复合材料的性能

采用表面原位接枝聚合在纳米CaCO3颗粒表面引入聚甲基丙烯酸甲酯(PMMA)或聚丙烯酸丁酯(PBA),用共混法制备了纳米CaC03/PVC复合材料,研究了不同界面特性时纳米CaCO,/PVC复合材料的力学性能.研究结果表明:通过表面原位接枝聚合反应可以在纳米CaCO3颗粒表面接枝PMMA和PBA;表面接枝聚合改性大大促进了纳米CaCO3粒子在PVC基体中的分散行为,增加了复合材料的拉伸强度以及与聚合物的界面粘接强度,但复合材料的冲击强度有所下降.