共查询到19条相似文献,搜索用时 125 毫秒
1.
《现代塑料加工应用》2019,(5)
采用化学发泡注射成型技术制备了发泡聚丙烯(PP)复合材料,研究了不同成核剂(NA)含量对其发泡行为和力学性能的影响。结果表明:NA的加入为泡孔成核提供了大量的成核位点,有效改善了发泡PP复合材料的泡孔结构、尺寸分布和泡孔密度;当NA质量分数为5‰时,发泡材料泡孔平均直径最小约125μm,泡孔密度最大约2.54×10~5个/cm~3,泡孔尺寸分布较好。另一方面,随着NA含量的增加,发泡PP复合材料的拉伸强度、弯曲强度和弯曲模量呈增加趋势。 相似文献
2.
3.
4.
竹粉对微发泡聚丙烯发泡行为的影响 总被引:1,自引:1,他引:0
通过改性的竹粉,以不同含量加入到聚丙烯中,在二次开模条件下制备微发泡PP/竹粉复合材料,分析了不同含量的竹粉对微发泡复合材料发泡行为的影响规律。结果表明:随竹粉含量的增加,泡孔平均直径逐渐减小,泡孔密度逐渐增加,竹粉质量分数为7%时泡孔平均直径最小为22.3μm,泡孔密度达到2.92×107个/cm3,具有理想的发泡效果。 相似文献
5.
6.
7.
以不同含量的改性的碱式硫酸镁(MgSO4)晶须加入到聚丙烯(PP)中,在二次开模条件下制备微发泡PP/硫酸镁晶须复合材料,分析了不同含量的硫酸镁晶须对微发泡复合材料发泡行为的影响规律。结果表明,随晶须含量的增加,泡孔平均直径逐渐减小,泡孔密度逐渐增加,晶须质量分数为25%时泡孔直径为26.79μm,泡孔密度达到2.33×105个/cm3,具有理想的发泡效果。 相似文献
8.
9.
10.
11.
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。 相似文献
12.
Investigation of the microstructures,properties, and toughening mechanism of polypropylene/calcium carbonate toughening masterbatch composites 下载免费PDF全文
The morphologies, crystallization and melting behaviors, and mechanical, thermal and processing properties of polypropylene (PP)/CaCO3 toughening masterbatch (CTM) composites were investigated. The good dispersion of CaCO3 particles via appropriate surface encapsulation in the composites is proven by density measurements and scanning electron microscopy images. The crystallinity and tensile strength of PP decrease with the addition of CTM. The flexural modulus and storage modulus (E′) at 23 °C increase with CTM content, implying improved stiffness. A sharp increase in the Izod notched impact strength can be observed for the composites, and the critical ligament thickness (τc) is calculated to be 1.31 and 2.46 μm for PP (S1003) and PP (001 G) composites, respectively. The morphologies of the impact‐fractured surfaces of the specimens were observed, and the shear deformation is enhanced by the addition of CTM. The presence of CTM also increases the melt flowability and decreases the shrinkage of the composites. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45515. 相似文献
13.
Polypropylene composites containing 0–5 wt% layered silicate and 0–30 wt% short glass fibers are prepared by melt compounding. To investigate the influence of different compositions on the mechanical properties of short glass fiber‐reinforced polypropylene nanocomposites, materials with various filler contents are prepared. At a glass fiber content of 10 wt% Young's modulus of the layered silicate‐containing composites decreases by around 30% compared to conventional glass fiber‐reinforced polypropylene. But at higher glass fiber loadings, an increasing modulus of up to 10% is observed. However, the addition of layered silicate results in large decreases of the tensile and the notched impact strength. A maleic anhydride‐grafted polypropylene enhances Young's modulus and the tensile strength. © 2012 Society of Plastics Engineers 相似文献
14.
15.
采用硝酸液相氧化法改性短切碳纤维(NCF),用以制备聚丙烯(PP)复合材料。以纤维含量和纤维种类为变量,通过万能力学试验机、熔体流动速率试验机、差示扫描量热、X射线衍射、扫描电子显微镜等研究它们对材料力学性能、流动性能、熔融温度以及结晶性能的影响。实验结果表明,纤维的含量影响纤维在基体中的分布,进而显著影响材料的性能,且含量在10%至20%区内时具有较好的增强效果;NCF与PP的界面具有更强的粘附力,这提升了复合材料的力学强度,降低了材料的断裂伸长率,降低了材料的熔融流动速率,提升了材料的结晶温度与结晶度,略微降低了材料的熔融温度;纤维含量与纤维种类均对材料的结晶晶型无明显影响。 相似文献
16.
硅灰石与连续玻璃纤维毡组合增强聚丙烯的力学性能 总被引:8,自引:0,他引:8
采用硅灰石与连续玻璃纤维毡组合增强聚丙烯,研究了硅灰石的含量,玻璃纤维毡的面密度、基体树脂的性质及界面改性等对材料力学性能的影响。结果表明:采用硅灰石与连续玻璃纤维毡组合增强,可提高复合材料的拉伸、弯曲强度及模量,但过高的硅灰石含量,会导致拉伸及弯曲强度下降,材料的力学性能随着所用玻璃纤维毡面密度的增大而显著提高,采用偶联剂对硅灰石进行处理及在基体聚丙烯中添加功能化聚丙烯,可改善界面结合、提高材料性能,随着功能化聚丙烯含量的增加,材料的拉伸、弯曲强度及模量有所提高,但含量过高时,会引起材料冲击强度的下降;组合增强材料的性能与基体树脂本身的力学性能密切相关,同时还受基体树脂熔体流动性的影响。 相似文献
17.
This study was aimed at fabrication of green composites of polypropylene (PP) matrix 5, 10, 15, and 20 wt% of saw palmetto spent (SPS) (a spent of nutraceuticals) as filler material. Two wt% organically modified montmorillonite clay (MMT) was used as a co‐filler in all formulations and composites were fabricated by melt blending. The fabricated PP/SPS/MMT composites were characterized for physicomechanical and tribological properties. Improvement in tensile modulus of the composites was noticed with increase in SPS content. The tensile strength of composites was decreased by 14% with increase in filler content from 5 to 20 wt%. Flexural strength of the composites increased from 31.3 to 37.8 MPa (21% improvement) and also flexural modulus improved from 956 to 1383 MPa (45% improvement) with increased SPS content. Composites were subjected to three‐body abrasion with different loads and abrading distances. Scanning electron microscope (SEM) study revealed that the predominant wear mechanisms of composite material sliding against continuous flowing sand were microploughing and filler detachment from the polymer matrix. POLYM. COMPOS., 37:2306–2312, 2016. © 2015 Society of Plastics Engineers 相似文献
18.
为了提高聚丙烯(PP)的导热性能,扩大其使用范围,采用价格低廉的商用石墨对PP进行改性,利用转矩流变仪制备了PP/石墨导热复合材料。研究了粒径为2μm和20μm的石墨及其复配对复合材料热导率及力学性能的影响。结果表明,复合材料的热导率随着石墨用量的增加而显著增大,20μm石墨填充的复合材料热导率高于2μm石墨填充的复合材料;由于石墨的各向异性,层内热导率远高于层间热导率;将两种粒径的石墨复配,固定石墨总质量分数为40%,当2μm石墨与20μm石墨质量比为1︰5时,复合材料层间和层内热导率达到最大,分别为1.125 W/(m·K)和2.897 W/(m·K),比相同用量下单一2μm石墨填充PP分别提高了121%和61%,比单一20μm石墨填充PP分别提高了3.6%和20%。随石墨用量增加,单一粒径石墨填充的复合材料拉伸强度和弯曲强度呈现先减小后增大的趋势,随复配填料中20μm石墨用量增加,复配填料填充复合材料的力学性能呈下降趋势,但弯曲强度变化不大,拉伸强度也在10 MPa以上。 相似文献
19.
采用双螺杆挤出机制备了一系列聚丙烯(PP)/木粉/纳米凹凸棒土(AT)木塑复合材料(WPC.研究了AT用量对复合材料力学性能、热性能、加工性能的影响.结果表明,随着AT用量的增加,复合材料拉伸强度逐渐增加、冲击强度逐渐减小,硬度先增加后减小,AT用量为5份时复合材料硬度最大;复合材料维卡软化点不断提高;熔体流动速率(M... 相似文献