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HDPE/木粉复合材料的性能研究 总被引:1,自引:0,他引:1
研究了不同种类的增容剂对高密度聚乙烯(HDPE)木/粉复合材料性能的影响,并研究了增容剂含量、木粉含量对复合材料力学性能及形态结构的影响。结果表明,HDPE木/粉复合材料的拉伸强度、弯曲强度均随马来酸酐接枝HDPE(HDPE-g-MAH)含量的增加而增大;复合材料的缺口冲击强度随甲基丙烯酸缩水甘油酯接枝低密度聚乙烯的增加而提高;复合材料的拉伸强度、弯曲强度随木粉含量的增加而增大;而缺口冲击强度则随木粉含量的增加呈降低趋势。 相似文献
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以聚丙烯(PP)/高密度聚乙烯(HDPE)共混物为基体,六方氮化硼(h-BN)为导热填料,聚丙烯接枝马来酸酐(PP-g-MAH)为相容剂,通过熔融共混法制备PP/HDPE/h-BN和PP/HDPE/h-BN/PP-g-MAH导热复合材料。采用导热系数仪、场发射扫描电镜、万能试验机、热分析仪等测试导热复合材料,研究不同含量的h-BN、PP-g-MAH对复合材料导热性、力学性能、结晶性能和耐热性的影响。结果表明:随着h-BN含量的增加,PP/HDPE/h-BN复合材料的弯曲强度、热导率和耐热性提高。当h-BN含量为20%,复合材料的弯曲强度达到41.02 MPa;当h-BN含量为25%,复合材料热导率达到0.372 1 W/(m·K)。h-BN对PP的结晶具有促进作用,提升PP的结晶速率和结晶温度。PP、HDPE与h-BN质量比为64∶16∶15时,添加5%的PP-g-MAH,增强了h-BN和基体材料的界面相容性,复合材料的弯曲强度达到42.72 MPa,拉伸强度达到26.64 MPa,热导率达到0.356 1 W/(m·K)。 相似文献
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为提高木质素与高密度聚乙烯(HDPE)的相容性,以乙烯基三乙氧基硅烷(TEVS)作为表面改性剂对木质素进行疏水化预处理,采用开炼-热压法制备高密度聚乙烯/乙烯基硅烷改性木质素(HDPE/TEVS-Lig)复合材料。研究TEVS对HDPE/TEVS-Lig力学性能的影响,TEVS-Lig对HDPE/TEVS-Lig的界面相容性、力学性能、熔融结晶性能和热稳定性的影响。结果表明:TEVS被成功引入木质素表面,颗粒均匀性显著提高。当TEVS含量为0.6%,HDPE/TEVS-Lig力学性能最优。当TEVS-Lig含量为3%,TEVS-Lig与HDPE两相界面呈连续相,拉伸强度以及断裂伸长率达到最优。随着TEVS-Lig含量的增加,HDPE/TEVS-Lig的熔融温度先升高后降低,而结晶温度和结晶焓整体上均提高。TEVS-Lig虽然降低了HDPE/TEVS-Lig的热稳定性,但能够提高HDPE/TEVS-Lig的残炭率。 相似文献
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研究了乙烯-醋酸乙烯共聚物(EVA)增容高密度聚乙烯(HDPE)和聚碳酸酯(PC)共混体系,讨论了EVA,PC对HDPE/PC共混合金性能的影响。结果表明:随PC用量的增加,HDPE/PC共混合金的熔体流动速率减小,缺口冲击强度增大,拉伸强度增大,维卡软化点变化不大。EVA能够改善合金体系的加工流动性,却明显降低了合金体系的力学性能。 相似文献
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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。 相似文献
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In this article, tensile properties have been discussed in terms of phase morphology, crystallinity and molecular orientation in the HDPE/iPP blends, prepared via dynamic packing injection molding, with aid of scanning electron microscopy (SEM), differential scanning calorimetry (DSC) as well as two dimensional X-ray scattering (2D WAXS). For the un-oriented blends, the tensile properties (tensile strength and modulus) are mainly dominated by the phase morphology and interfacial adhesion related to the influenced crystallization between HDPE and iPP component. A maximum in tensile strength and modulus is found at iPP content in the range of 70-80 v/v%. As for the oriented blends, however, the presence of dispersed phase in the blends, independent of phase morphology and crystallinity, always makes tensile properties to be deteriorated through reducing molecular orientation of matrix. It is molecular orientation of matrix that determines the tensile properties of oriented blends. In the blends with HDPE as matrix, steep decreasing of tensile properties is related to the rapid reducing of molecular orientation of HDPE, whereas in the blends with iPP as a major component, slight decreasing of molecular orientation of iPP results in slight reducing of tensile properties. Other factors, such as interfacial properties and phase morphology, seem to be little contribution to the modulus and tensile strength. 相似文献
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利用乙烯基聚二甲基硅氧烷/苯乙烯接枝型长支链聚丙烯(PP-g-VS/St)在剪切和快速降温过程中可以诱导形成β晶聚丙烯这一优势,研究了PP-g-VS/St在注塑加工过程中作为高分子β晶成核剂对等规聚丙烯(iPP)结晶温度、晶体结构及力学性能的影响。结果表明改性聚丙烯的结晶温度、β晶相对含量和力学性能随着PP-g-VS/St添加量的增加而增加。当PP-g-VS/St的添加量为50%(质量分数)时,改性聚丙烯的结晶温度相对于纯iPP提高约10℃,β晶相对含量达32.8%,冲击强度、弯曲模量和拉伸强度分别相对于纯iPP提高了355.3%、53.8%和15.9%。这些结果为聚丙烯高分子β晶型成核剂的设计提供了新思路。 相似文献
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用熔融共混法制备了高密度聚乙烯/聚丙烯(HDPE/PP)和乙烯-辛烯弹性体/高密度聚乙烯/聚丙烯(POE/HDPE/PP)复合材料。通过冲击、弯曲和拉伸测试研究了复合材料的力学性能,采用扫描电镜(SEM)观察了材料的形貌。结果表明,由于HDPE和PP的相容性有限,限制了HDPE对PP综合力学性能的提高;通过添加POE,能改善HDPE/PP共混物的相容性,使HDPE/PP复合材料在保持较高弯曲和拉伸性能的前提下,抗冲击性能获得明显提高。当HDPE/PP的含量比为12/88和POE含量为8wt%时,POE/HDPE/PP三元复合材料的综合力学性能较好。 相似文献
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Saeed Doroudiani Chul B. Park Mark T. Kortschot 《Polymer Engineering and Science》1998,38(7):1205-1215
In this paper, a study on the batch processing and characterization of microcellular foamed high-density polyethylene (HDPE/iPP) blends is reported. A microcellular plastic is a foamed polymer with a cell density greater than 109 cells/cm3 and fully grown cells smaller than 10 µm. Recent studies have shown that the morphology and crystallinity of semicrystalline polymers have a great influence on the solubility and diffusivity of the blowing agent and on the cellular structure of the resulting foam in microcellular batch processing. In this research, blends of HDPE and iPP were used to produce materials with variety of crystalline and phase morphologies to enhance the subsequent microcellular foaming. It was possible to produce much finer and more uniform foams with the blends than with neat HDPE and iPP. Moreover, the mechanical properties and in particular the impact strength of the blends were significantly improved by foaming. 相似文献
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The mechanical and thermal characteristics and morphology of polyamide 6 (PA6)/isotactic polypropylene (iPP) blends (10/90 w/w) prepared with different processing procedures and incorporated with an aryl amide nucleating agent, a kind of β‐nucleating agent (β‐NA) for iPP, were investigated. The yield strength and flexural modulus of the blends decreased as β‐NA was introduced into the blends, whereas the impact strength and elongation at break improved. The crystalline structures of the blends closely depended on (1) the processing conditions and (2) competition between the β‐nucleating effect of β‐NA and the α‐nucleating effect of PA6 for iPP. Scanning electron microscopy, differential scanning calorimetry, and X‐ray diffraction were adopted to reveal the microstructures of the blends. At a low β‐NA content (<0.1 wt %), the α‐phase iPP dominated the blends, whereas the relative content of the β‐phase iPP increased remarkably when the β‐NA content was not less than 0.1 wt %. The processing conditions also showed profound influences on the supermolecular structures of iPP; this resulted in different mechanical properties of the blends. As for PA6, the crystallization behavior and crystalline structure did not exhibit obvious changes, but PA6 did play an important role in the epitaxial crystallization of iPP on PA6. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
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为了增强等规聚丙烯(iPP)的透明性能和冲击性能,采用物理共混方法,将弹性体氢化聚苯乙烯—丁二烯—聚苯乙烯嵌段共聚物(SEBS)与NX8000K成核剂配合使用对iPP进行改性。通过差示扫描量热分析(DSC)和X射线衍射分析(XRD)、偏光显微镜分析(POM)等方法研究了SEBS对iPP/NX8000K组合物的结晶行为、透明性能和力学性能的影响。结果表明:在NX8000K含量为0.6 %(质量分数,下同),SEBS用量为40 %时,iPP/NX8000K/SEBS三元组合物的雾度降至24.9 %,比纯iPP降低了54.7 %;冲击强度增至50.7 kJ/m2,与纯iPP相比提高了10倍。 相似文献
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Summary Ternary mixtures of isotactic polypropylene (iPP), high density polyethylene (HDPE) and hydrogenated oligo(cyclopentadiene) (HOCP) commercial products were prepared by melt mixing. The crystallization behaviour of iPP/HDPE and (iPP/HDPE)/HOCP systems were compared. It was shown that the ternary system separated in two binary systems. The presence of HOCP modified the morphology of iPP and HDPE phases. The polyolefins nucleation and crystal growth rates decreased due to the diluent effect of the oligomer. HDPE showed higher compatibility with HOCP than iPP. 相似文献
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Glass beads were used to improve the mechanical and thermal properties of high‐density polyethylene (HDPE). HDPE/glass‐bead blends were prepared in a Brabender‐like apparatus, and this was followed by press molding. Static tensile measurements showed that the modulus of the HDPE/glass‐bead blends increased considerably with increasing glass‐bead content, whereas the yield stress remained roughly unchanged at first and then decreased slowly with increasing glass‐bead content. Izod impact tests at room temperature revealed that the impact strength changed very slowly with increasing glass‐bead content up to a critical value; thereafter, it increased sharply with increasing glass‐bead content. That is, the Izod impact strength of the blends underwent a sharp transition with increasing glass‐bead content. It was calculated that the critical interparticle distance for the HDPE/glass‐bead blends at room temperature (25°C) was 2.5 μm. Scanning electron microscopy observations indicated that the high impact strength of the HDPE/glass‐bead blends resulted from the deformation of the HDPE matrix. Dynamic mechanical analyses and thermogravimetric measurements implied that the heat resistance and heat stability of the blends tended to increase considerably with increasing glass‐bead content. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2102–2107, 2003 相似文献
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Xiaoli Zhang Baojia Sun Guoyuan Yuan Shixun Zhang Youxin Ji Baochen Liu Mingxin Zhang Yang Yang Jingbo Chen 《应用聚合物科学杂志》2021,138(18):50342
This study presents a self-designed foaming apparatus and routes to manufacture foamed isotactic polypropylene (iPP) blends with uniform and dense cells, using styrene-ethylene-butadiene-styrene (SEBS) block copolymer as toughening additive. The addition of SEBS can clearly enhance the impact strength of solid iPP, iPP blends with a 20 wt% SEBS has obtained high notched impact strength of 75 kJ/m2, which is ca. 16 times larger than that of neat iPP. Relatively fine microcellular iPP-SEBS foams with the average cell size of several micrometers, and the cell density of 109 cells/cm3 were fabricated using a batch foaming procedure. Moreover, using our self-designed mold and compression foaming method, iPP-SEBS foams with balanced mechanical properties were produced. With the increasing of SEBS, tensile strength and flexural strength were slightly decreased, but the impact strength was increased clearly. The balanced mechanical properties between stiffness and toughness were achieved after compression foaming. 相似文献