Polypropylene‐organoclay nanocomposite: Preparation,microstructure, and mechanical properties

A series of polypropylene (PP) nanocomposites containing 2, 4, and 6 wt % of an organophilic montmorillonite clay was prepared via direct melt mixing in the presence of maleic anhydride grafted polypropylene (PP‐g‐MAH) as compatibilizing agent. Microstructure characterization was performed by X‐ray diffraction analysis. Nanocomposites exhibited a 15 and 22% enhancement in tensile modulus and impact strength, respectively. The heat deflection temperature of PP nanocomposites was 36°C greater than for pure PP. Thermal and mechanical properties of nanocomposites were compared to properties of traditional PP‐talc and PP‐glass fiber composites. The results showed that the properties of nanocomposites improved compared to ordinary polypropylene composites. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Mechanical properties of modified biofiller‐polypropylene composites

This article reports the mechanical, thermal, and morphological properties of polypropylene (PP)‐chicken eggshell (ES) composites. Mechanical properties like tensile strength, tensile modulus, izod impact strength, flexural modulus of PP composites with normal (unmodified) eggshell and chemically treated ES [modified ES (MES) with isophthalic acid] have been investigated. PP–calcium carbonate (CaCO₃) composites, at the same filler loadings, were also prepared and used as reference. The results showed that PP composites with chemically MES had better mechanical properties compared to the unmodified ES and CaCO₃ composites. An increase of about 3–18% in tensile modulus, 4–44% in izod impact strength and 1.5–26% in flexural modulus at different filler loading was observed in MES composites as compared to unmodified ES composites. Scanning electron microscopy (SEM) micrographs of fractured tensile specimens confirmed better interfacial adhesion of MES with polymer matrix resulting into lower voids and plastic deformation resulting in improved mechanicals of the composites. TEM micrographs showed acicular needle shaped morphology for modified ES and have contributed to better dispersion which is the prime reason for enhancement of all the mechanical properties. At higher filler loading, the modulus of MES composite was found to be higher by 5% as compared to commercial CaCO₃ composites. POLYM. COMPOS., 35:708–714, 2014. © 2013 Society of Plastics Engineers     

硅烷表面修饰氧化铝对聚丙烯的力学和耐热性能的影响

以3%氧化铝(Al2O3)或3种硅烷偶联剂表面修饰过的氧化铝为增强剂,采用高速混合与熔融挤出结合方法制备Al2O3/聚丙烯(PP)复合材料。研究硅烷表面修饰氧化铝对PP力学性能和耐热性能的影响。结果表明,采用硅烷偶联剂γ-巯丙基三甲氧基硅烷(KH590)对氧化铝表面修饰后,Al2O3/PP复合材料的性能得到改善。拉伸强度由33.80 MPa略降至32.63 MPa,冲击强度由14.58 kJ/m2增加至19.79 kJ/m2,拉伸模量由0.25 GPa增加至0.27 GPa,邵氏硬度D由75增加到84;同时Al2O3/PP复合材料的耐热性能有明显提高。     

MAH/St固相接枝聚丙烯对聚丙烯/滑石粉复合材料性能的影响

利用马来酸酐（MAH）/苯乙烯（St）共单体固相接枝聚丙烯（MSP）作增容剂,采用熔融共混和注塑成型的方法制备了PP/滑石粉复合材料,研究了MSP对PP/滑石粉复合材料热行为、拉伸强度和动态力学性能的影响.结果显示MSP降低了PP/滑石粉复合材料中PP相的熔融温度（Tm）,但随着增容剂MSP含量的增加,Tm呈上升趋势.MSP改善了PP/滑石粉间的相容性,促进了滑石粉的异相成核作用,提高了PP相的Tco随着MSP含量的提高,Tc呈下降趋势.MSP增容剂提高了PP/MSP/滑石粉复合材料的拉伸强度和动态贮能模量,并存在一最佳的增容剂添加量.     

聚丙烯/纳米钛合金复合材料耐候性研究

将纳米钛合金与聚丙烯(PP)经熔融共混制得PP/纳米钛合金复合材料,研究了PP及其复合材料在大气暴露条件下的耐候性,利用傅立叶变换红外光谱仪分析了老化前后PP及其复合材料的化学结构。结果表明,纳米钛合金能明显地改善PP的耐候性。在大气条件下暴露90d后,复合材料的断裂伸长率和缺口冲击强度保持率明显高于纯PP;复合材料的拉伸强度、拉伸弹性模量甚至还高于暴露前的值,而纯PP的拉伸强度则小于暴露前的值,拉伸弹性模量的增幅也小于复合材料。     

Preparation and evaluation of composites containing polypropylene and cotton gin trash

Composites of polypropylene (PP) and cotton gin trash (GT) were prepared to enhance the utilization of agro-based materials in industrial products. GT was modified by two methods: toluene washed only, and toluene washed and treated with maleic anhydride-grafted polypropylene (MAPP). These GT samples were extruded with PP, including MAPP and ethylene/vinyl acetate copolymer in various weight ratios (32 composites total). The PP composites displayed tensile strengths close to that of the neat PP, and exhibited higher values of tensile modulus and lower elongation at break than the neat PP. Based on DSC measurements, the PP composites containing 10 wt% GT exhibited two crystalline regimes, while those containing 20 wt% GT were similar in crystallinity to that of the neat PP. The composites were also characterized using SEM, TGA, water absorption tests, and contact angle measurements. These composites represent a more sustainable alternative to neat, fossil fuel-based PP.     

玻纤增强PP热塑性片材的制备及力学性能研究

采用熔融浸渍法制备了玻璃纤维毡增强聚丙烯（PP）热塑性复合片材；通过在PP中加入复合改性PP改善了基体与增强纤维间的相容性；考察了相容剂、PP种类及玻纤毡种类对复合片材的影响。结果表明，相容剂的加入可使复合片材的拉伸强度提高29％、拉伸模量提高23％、弯曲强度提高42％、弯曲模量提高25％；高熔体质量流动速率PP可使片材的弯曲与冲击性能进一步改善。连续玻纤毡和长玻纤毡增强PP复合片材，前者综合力学性能良好，而后者则冲击强度较弱、弯曲性能加强。     

Study on the Effect of Polypyrrole and Polypyrrole/Graphene Oxide Nanoparticles on the Microstructure,Electrical and Tensile Properties of Polypropylene Nanocomposites

In this article Polypropylene/Polypyrrole (PP/PPy) and Polypropylene/polypyrrole-graphene oxide (PP/PPy-GO) nanocomposites were prepared by melt mixing. PPy nanoparticles and PPy-GO nanocomposite were prepared by chemical polymerization and served as nanofillers. FTIR, XRD and SEM analysis were used for the characterization of PPy and PPy-GO composites. The effects of PPy and PPy-GO loading level on the morphology, tensile and electrical properties of PP-based nanocomposites were examined. It was found that the Young's modulus and tensile strength increased with the increase of nanofiller content. Tensile results also showed that PPy-GO composite significantly affected the mechanical properties of PP based nanocomposites compared to the PPy nanoparticles. It was observed that the addition of 1% wt. PPy-GO into PP, increased the Young's modulus about 30% compared as with pure PP. Electrical conductivity measurements showed that conductivity of PP nanocomposites increased up to 1 × 10^?3 S/cm for PP/PPy-GO nanocomposites. It was also observed that PP-g-MA improved the distribution of PPy and PPy-GO nanocomposites and affected the morphology, electrical and mechanical properties of PP-based nanocomposites.     

Chemical Modification of Chitosan-Filled Polypropylene (PP) Composites: The Effect of 3-Aminopropyltriethoxysilane on Mechanical and Thermal Properties

Chitosan was used as filler in polypropylene (PP) polymer. In order to improve compatibility between chitosan and PP, chitosan was chemically modified with 3-aminopropyltriethoxysilane (3-APE). The results show that the increasing of filler content decreased tensile strength and elongation at break, but increased Young's modulus of composites. The treated composites exhibit higher tensile strength and Young's modulus, but lower elongation at break compared untreated composites. The addition of 3-APE has improved thermal properties such as thermal stability and crystallinity of treated composites. SEM study of the tensile fracture surface of treated composites shows better interfacial interaction and adhesion between the chitosan-PP matrix.     

凹凸棒土表面改性及其对聚丙烯力学性能的影响

使用硬脂酸钠、硅烷和钛酸酯偶联剂对凹凸棒土进行了表面改性,通过熔融共混法制备PP/凹凸棒土复合材料。借助FTIR、DSC、TEM、材料力学实验机等手段分别对凹凸棒土的改性效果、分散状态以及复合材料的结构与性能进行了研究。结果表明,适当的表面修饰有助于凹凸棒土在PP基体中实现以针状棒晶为基本形态的均匀分散;凹凸棒土在基体中提高了PP结晶度的同时提高了材料的强度和模量。     

Nanocomposites based on poly(butylene adipate‐co‐terephthalate) and montmorillonite

Nanocomposites based on biodegradable poly(butylene adipate‐co‐terephthalate) (PBAT) and layered silicates were prepared by the melt intercalation method. Nonmodified montmorillonite (MMT) and organo‐modified MMTs (DA‐M, ODA‐M, and LEA‐M) by the protonated ammonium cations of dodecylamine, octadecylamine, and N‐lauryldiethanolamine, respectively, were used as the layered silicates. The comparison of interlayer spacing between clay and PBAT composites with inorganic content 3 wt % measured by X‐ray diffraction (XRD) revealed the formation of intercalated nanocomposites in DA‐M and LEA‐M. In case of PBAT/ODA‐M (3 wt %), no clear peak related to interlayer spacing was observed. From morphological studies using transmission electron microscopy, the ODA‐M was found to be finely and homogeneously dispersed in the matrix polymer, indicating the formation of exfoliated nanocomposite. When ODA‐M content was increased, the XRD peak related to intercalated clay increased. Although the exfoliated ODA‐M (3 wt %) nanocomposite showed a lower tensile modulus than the intercalated DA‐M and LEA‐M (3 wt %) composites, the PBAT/ODA‐M composite with inorganic content 5 wt % showed the highest tensile modulus, strength, and elongation at break among the PBAT composites with inorganic content 5 wt %. Their tensile properties are discussed in relation to the degree of crystallinity of the injection molded samples. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 386–392, 2005     

自制光稳定剂HWPAN-g-TiO2与几种光稳定剂对聚丙烯性能的对比研究

利用废旧腈纶织物制备了一种聚丙烯（PP）用大分子紫外屏蔽吸收类型光稳定剂,利用其和通用的受阻酚类光稳定剂分别制备耐候性PP复合材料,并进行了人工加速老化实验。探究了大分子紫外屏蔽吸收类型光稳定剂在PP老化过程中对PP老化降解的影响,并与通用的受阻酚类光稳定剂进行了对比研究。结果表明,大分子紫外屏蔽吸收类型光稳定剂效果明显,在人工加速老化500 h之后,PP的羰基指数高达150.3;而PP/HWPAN-g-TiO2仅为53,与此同时,PP的拉伸强度从25 MPa降至6.9 MPa,下降了72.4 %;而PP/HWPAN-g-TiO2的拉伸强度从29 MPa降至25 MPa,下降13.8 %。     

Effects of preparation methods on the property of PMMA/SBA-15 mesoporous silica composites

In the paper, poly(methyl methacrylate)(PMMA)/SBA-15 composite materials were prepared by four different methods, that is, in-situ batch emulsion polymerization in the presence of mesoporous SBA-15, PMMA emulsion mixed with SBA-15 powder or dispersion in water, PMMA powder mixed with SBA-15 powder, and the properties of the composite materials were determined and compared. The composites were characterized by infrared spectroscopy (IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), dynamic mechanics analysis (DMA) and scanning electron microscope (SEM). The results showed that the glass transition temperatures (Tg), the storage modulus and tensile strength of the PMMA/SBA-15 composites were all improved obviously, while the thermal decomposition temperature did not influenced apparently. The composite made by in-situ batch polymerization exhibited the most improvement in the mechanical properties and Tg while the composite prepared by mixing PMMA emulsion and SBA-15 dispersion gave rise to the least improvement in the mechanical properties and Tg. These results were contributed to introducing different amount of voids into polymer matrix which were demonstrated by dielectric constant measurement and SEM morphology observation.     

Surface‐modified talc particles by acetoxy groups grafting: Effects on mechanical properties of polypropylene/talc composites

This article deals with the effects of surface‐modified talc particles on mechanical properties of polypropylene (PP)/talc composites. These materials were prepared by injection molding of PP blended with different concentrations of nontreated and treated talc, under the same processing conditions. Differential thermal calorimetry and scanning electron microscopy were used to assess thermal properties and morphology of the final composites. The reinforcing effect of talc, either treated or nontreated surface, on PP is analyzed through the tensile properties as a function of the mineral content (0–10 wt%). Morphological structure of composites revealed that the talc treatment improved the particle dispersion and distribution within the PP matrix and enhanced the interfacial PP‐talc adhesion. The mechanical properties of these composites, especially the Young modulus, tensile strength and elongation at break, were found to be improved respect to PP‐untreated talc ones. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers     

Elaboration of performance of tea dust–polypropylene composites

In this research work, dynamic, mechanical, and thermophysical properties of untreated and 5, 7, and 10 wt % styrene treated tea dust (TD):polypropylene (PP) composites prepared by injection‐molding machine were elaborated. There were distinctive and significant improvement observed in mechanical properties (tensile strength, tensile modulus, and elongation at break), physical analysis (water swelling), dynamic mechanical properties (storage modulus, loss modulus, and tan δ), and thermal behavior and surface morphological properties of styrene treated TD:PP (40:60) composites as compared to that of untreated one. The tensile strength (from 7.00 to 9.95 MPa), tensile modulus (from 350 to 715 MPa), storage modulus (from 8500 to ～10,500 MPa), and loss modulus (from ～150 to ～200 MPa) increased on 10 wt % styrene treatment of TD over the untreated TD:PP (40:60) composites. The styrene treated TD:PP (40:60) composites behaved as more elastic than their pure counterpart. Styrene treated TD:PP (40:60) composites were more thermally more stable (85 °C difference) as compared to virgin PP. Overall, this research also indicates the use of TD waste. An improvement in dispersion of styrene treated TD particles in PP was also observed in the preparation of the PP composites due to good compatibility of styrene with PP. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44750.     

回收聚丙烯/废书刊纸纤维复合材料结构与力学性能的研究

以废书刊纸纤维(OMGF)和回收聚丙烯(PP)为原料,马来酸酐接枝聚丙烯(MAPP)为相容剂,采用热压成型法制备了PP/OMGF木塑复合材料。研究了OMGF含量对复合材料拉伸性能及弯曲性能的影响,并采用红外光谱和扫描电子显微镜分析了OMGF的结构及复合材料的拉伸断面形貌。结果表明,OMGF对PP基体具有一定的增强作用,当OMGF含量为30%时,复合材料的拉伸强度和弯曲强度分别达到最大值29.53MPa和33.67MPa,比回收PP分别提高了51.6%和31.7%;随着OMGF含量的增加,复合材料的断裂伸长率逐渐下降,弯曲模量逐渐上升。扫描电子显微镜分析显示,当OMGF含量较低时,其与PP基体之间具有良好的界面相容性;当OMGF含量增加到50%时,界面相容性明显下降。     

The effect of dynamic vulcanization on mechanical properties and water absorption of silica and rubberwood filled polypropylene/natural rubber hybrid composites

Dynamic vulcanized silica and rubberwood filled polypropylene (PP)/natural rubber (NR) hybrid composites were prepared using a Brabender plasticorder at 150°C and a rotor speed of 50 rpm for 12 minutes. The effectiveness of the dynamic vulcanization was indicated by the Brabender plastograms. The mechanical and water absorption properties of hybrid composites with different concentration of sulfur were investigated. Significant enhancement in mechanical properties, viz. tensile strength, stress at peak, Young modulus and flexural modulus were observed for dynamically vulcanized hybrid composites compared to unvulcanized hybrid composites. This has been attributed to the increase in crosslink density, which was manifested by a reduction of water absorption and increase of stabilization torque at the end of mixing stage with increasing sulfur concentration.     

Thermal and mechanical properties of plasticized poly(L‐lactide) nanocomposites with organo‐modified montmorillonites

Nanocomposites of poly(lactide) (PLA) and the PLA plasticized with diglycerine tetraacetate (PL‐710) and ethylene glycol oligomer containing organo‐modified montmorillonites (ODA‐M and PGS‐M) by the protonated ammonium cations of octadecylamine and poly(ethylene glycol) stearylamine were prepared by melt intercalation method. In the X‐ray diffraction analysis, the PLA/ODA‐M and plasticized PLA/ODA‐M composites showed a clear enlargement of the difference of interlayer spacing between the composite and clay itself, indicating the formation of intercalated nanocomposite. However, a little enlargement of the interlayer spacing was observed for the PLA/PGS‐M and plasticized PLA/PGS‐M composites. From morphological studies using transmission electron microscopy, a finer dispersion of clay was observed for PLA/ODA‐M composite than PLA/PGS‐M composite and all the composites using the plasticized PLA. The PLA and PLA/PL‐710 composites containing ODA‐M showed a higher tensile strength and modulus than the corresponding composites with PGS‐M. The PLA/PL‐710 (10 wt %) composite containing ODA‐M showed considerably higher elongation at break than the pristine plasticized PLA, and had a comparable tensile modulus to pure PLA. The glass transition temperature (T_g) of the composites decreased with increasing plasticizer. The addition of the clays did not cause a significant increase of T_g. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci, 2006     

Morphological,mechanical, and physical properties of composites made with wood flour‐reinforced polypropylene/recycled poly(ethylene terephthalate) blends

Wood flour (WF)‐filled composites based on a polypropylene (PP)/recycled polyethylene terephthalate (r‐PET) matrix were prepared using two‐step extrusion. Maleic anhydride grafted polypropylene (MAPP) was added to improve the compatibility between polymer matrices and WF. The effects of filler and MAPP compatibilization on the water absorption, mechanical properties, and morphological features of PP/r‐PET/WF composites were investigated. The addition of MAPP significantly improved mechanical properties such as tensile strength, flexural strength, tensile modulus, and flexural modulus compared with uncompatibilized composites, but decreased elongation at break. Scanning electron microscopic images of fracture surface specimens revealed better interfacial interaction between WF and polymer matrix for MAPP‐compatibilized PP/r‐PET/WF composites. MAPP‐compatibilized PP/r‐PET/WF composites also showed reduced water absorption due to improved interfacial bonding, which limited the amount of absorbable water molecules. These results indicated that MAPP acts as an effective compatibilizer in PP/r‐PET/WF composites. POLYM. COMPOS., 38:1749–1755, 2017. © 2015 Society of Plastics Engineers     

剑麻纤维与晶须混杂增强聚丙烯复合材料

采用熔融共混和注塑成型方法制得了剑麻短纤维(SF)和CaSO4晶须混杂增强聚丙烯(PP)复合材料，研究了复合材料的热性能、微观结构和力学性能。结果表明，晶须提高了复合材料的热稳定性，阻碍了PP的结晶，降低了复合材料中PP相的结晶度和结晶速率；SF和晶须提高了复合材料的模量和韧性，但由于混杂增强复合材料弱界面键合的制约，晶须的高强性能并没有在复合材料中充分表现出来。