首页 | 官方网站   微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
In this article, polyamide 6 (PA6), maleic anhydride grafted ethylene‐propylene‐diene monomer (EPDM‐g‐MA), high‐density polyethylene (HDPE) were simultaneously added into an internal mixer to melt‐mixing for different periods. The relationship between morphology and rheological behaviors, crystallization, mechanical properties of PA6/EPDM‐g‐MA/HDPE blends were studied. The phase morphology observation revealed that PA6/EPDM‐g‐MA/HDPE (70/15/15 wt %) blend is constituted from PA6 matrix in which is dispersed core‐shell droplets of HDPE core encapsulated by EPDM‐g‐MA phase and indicated that the mixing time played a crucial role on the evolution of the core‐shell morphology. Rheological measurement manifested that the complex viscosity and storage modulus of ternary blends were notable higher than the pure polymer blends and binary blends which ascribed different phase morphology. Moreover, the maximum notched impact strength of PA6/EPDM‐g‐MA/HDPE blend was 80.7 KJ/m2 and this value was 10–11 times higher than that of pure PA6. Particularly, differential scanning calorimetry results indicated that the bulk crystallization temperature of HDPE (114.6°C) was partly weakened and a new crystallization peak appeared at a lower temperature of around 102.2°C as a result of co‐crystal of HDPE and EPDM‐g‐MA. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

2.
Preparation and morphology of Polyamide 6 (PA6)/high density polyethylene (HDPE)/Styrene/Ethylene–Butylene/Styrene grafted with maleic anhydride (SEBS‐g‐MA)/Modified clay nanocomposites were studied. Mixing was performed using melting process in an extruder co‐rotating twin screw. After etching the materials with boiling toluene and THF at room temperature, the morphology of sample checked by scanning electron microscopy (SEM) analyses. X‐ray diffraction (XRD) used for evaluation of the effects of organo‐clay addition in the structure of nanocomposites. XRD traces showed that the characteristic (001) peak of the nanocomposites shifted to the lower degree region. XRD and SEM results showed more uniformly distribution and dispersion of HDPE in the PA6 matrix. Better sample morphology obtained, regarding less distance, and more uniformity between nanoparticles. The mechanical properties like tensile strength, impact strength, hardness and thermal properties of these toughened nanocomposites are discussed in terms of the nanoclay, SEBS‐g‐MA contents and morphology. Adding nanoclay improved hardness of nanocomposites product but reduced toughness and thermal properties. Meanwhile the presence of SEBS‐g‐MA as a compatibilizer improved toughness, thermal properties, hardness property, and the balance properties are achieved. POLYM. ENG. SCI., 55:29–33, 2015. © 2014 Society of Plastics Engineers  相似文献   

3.
A functionalized high‐density polyethylene (HDPE) with maleic anhydride (MAH) was prepared using a reactive extruding method. This copolymer was used as a compatibilizer of blends of polyamide 6 (PA6) and ultrahigh molecular weight polyethylene (UHMWPE). Morphologies were examined by a scanning electron microscope. It was found that the dimension of UHMWPE and HDPE domains in the PA6 matrix decreased dramatically, compared with that of the uncompatibilized blending system. The size of the UHMWPE domains was reduced from 35 μm (PA6/UHMWPE, 80/20) to less than 4 μm (PA6/UHMWPE/HDPE‐g‐MAH, 80/20/20). The tensile strength and Izod impact strength of PA6/UHMWPE/HDPE‐g‐MAH (80/20/20) were 1.5 and 1.6 times as high as those of PA6/UHMWPE (80/20), respectively. This behavior could be attributed to chemical reactions between the anhydride groups of HDPE‐g‐MAH and the terminal amino groups of PA6 in PA6/UHMWPE/HDPE‐g‐MAH blends. Thermal analysis was performed to confirm that the above chemical reactions took place during the blending process. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 75: 232–238, 2000  相似文献   

4.
The formation of core‐shell morphology within the dispersed phase was studied for composite droplet polymer‐blend systems comprising a polyamide‐6 matrix, ethylene‐propylene‐diene terpolymer (EPDM) shell and high density polyethylene (HDPE) core. In this article, the effect of EPDM with different molecular weights on the morphology and properties of the blends were studied. To improve the compatibility of the ternary blends, EPDM was modified by grafting with maleic anhydride (EPDM‐g‐MAH). It was found that core‐shell morphology with EPDM‐g‐MAH as shell and HDPE as core and separated dispersion morphology of EPDM‐g‐MAH and HDPE phase were obtained separately in PA6 matrix with different molecular weights of EPDM‐g‐MAH in the blends. DSC measurement indicated that there may be some co‐crystals in the blends due to the formation of core‐shell structure. Mechanical tests showed that PA6/EPDM‐g‐MAH/HDPE ternary blends with the core‐shell morphology exhibited a remarkable rise in the elongation at break. With more perfect core‐shell composite droplets and co‐crystals, the impact strength of the ternary blends could be greatly increased to 51.38 kJ m?2, almost 10 times higher than that of pure PA6 (5.50 kJ m?2). POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers  相似文献   

5.
This work is aim to study the encapsulated morphology development in ternary blends of polyamide 6/high density polyethylene/maleic anhydride‐grafted‐ethylene propylene diene monomer (PA6/HDPE/EPDM‐g‐MA) and polyamide 6/maleic anhydride‐grafted‐high density polyethylene/ethylene propylene diene monomer (PA6/HDPE‐g‐MA/EPDM) through thermodynamically control described by Harkins spreading theory. The phase morphology was confirmed by using scanning electron microscope (SEM) and selective solvent extraction revealed that PA6/HDPE/EPDM‐g‐MA blend having a composition of 70/15/15 vol % is constituted of polyamide 6 matrix with dispersed composite droplets of HDPE subinclusions encapsulated by EPDM‐g‐MA phase, while for PA6/HDPE‐g‐MA/EPDM blend with the same composition is constituted of polyamide 6 matrix with dispersed composite droplets of HDPE‐g‐MA subinclusions encapsulated by EPDM phase. Quiescent annealing test revealed that for PA6/HDPE/EPDM‐g‐MA blend, a perfect core–shell structure with one HDPE particle encapsulated by EPDM‐g‐MA phase was formed during annealing, and for PA6/HDPE‐g‐MA/EPDM blend, a novel complete inverting HDPE‐g‐MA/EPDM core/shell structure was achieved. Moreover, quantitative analysis about coalescent behaviors of HDPE‐g‐MA and HDPE subinclusions during quiescent annealing were investigated by image analysis and the result suggested that the grafted maleic anhydride group in HDPE‐g‐MA, acted as a role of steric repulsion, could suppress coalescence effects, thus leaded to a lower coalescent rate than that of HDPE subinclusions. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39937.  相似文献   

6.
The intumescent fire retardant polypropylene (IFP/PP) filled with ammonium polyphosphate (APP), melamine (M), and PA6 (charring agent) is discussed. Intumescing degree (ID) and the char yield were determined. Only when the three main components of IFR coexist at appropriate proportions, it has optimal ID and higher char yield. The appropriate proportion is PA6 : APP : M = 10 : 10 : 5. A new compatibilizer, carboxylated polypropylene (EPP), was added to PP/PA‐6 blend. Flow tests indicated that the apparent viscosity increased with the addition of EPP, thermal characterization suggested that EPP has reacted with PA6, PA6‐g‐EPP cocrystallized with PA6, and EPP‐g‐PA6 cocrystallized with PP; SEM micrographs illustrated that the presence of EPP improved the compatibility of PP and PA6. All the investigations showed that EPP was an excellent compatibilizer, and it was a true coupling agent for PP/PA6 blends. Using PA6 as a charring agent resulted in the IFR/PP dripping, which deteriorated the flammability properties. The addition of nano‐montmorillonite (nano‐MMT) as a synergistic agent of IFR enabled to overcome the shortcoming. The tensile test testified that the addition of nano‐MMT enhanced the mechanical strength by 44.3%. SEM showed that nano‐MMT improved the compatibility of the composites. It was concluded that the intumescent system with nano‐MMT was an effective flame retardant in improving combustion properties of polypropylene. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 739–746, 2006  相似文献   

7.
无卤阻燃EVA电缆专用料的配方优化   总被引:2,自引:1,他引:1  
通过基体树脂复配、自制相容剂(E-g-M)增容以及E-g-M与三元乙丙橡胶(EPDM)并用等途径对乙烯-醋酸乙烯酯共聚物(EVA)/氢氧化镁(MH)/微胶囊化红磷(RP)无卤阻燃电缆料(EMP)性能进行了优化.结果表明:EVA与高密度聚乙烯(HDPE)复配可有效提高EMP电缆料的拉伸强度,EVA与HDPE的质量比为3:1时,EMP/HDPE电缆料的拉伸强度可由7.2 Mpa提高到9.7 Mpa;当在EMP/HDPE电缆料中添加12份E-g-M时,EMP/HDPE电缆料的拉伸强度由9.7 Mpa增至12.8 Mpa,冲击强度由26.5 kJ/m~2升至29.4 kJ/m~2,断裂伸长率由63.7%增至97.8%,E-g-M对EMP/HDPE电缆料起到了同时增强、增韧的作用;当EMP/HDPE/E-g-M电缆料中加入5份EPDM时,EMP/HDPE/E-g-M电缆料的韧性得到了进一步提高,冲击强度和断裂伸长率分别增至35.8 kJ/m~2和162.2%,并且两者的加入对EMP电缆料的拉伸性能、阻燃性能及加工性能影响较小.对照低烟无卤阻燃护套料的技术性能标准(YD/T 1113-2001),EMP/HDPE/E-g-M/EPDM电缆料的力学性能和阻燃性能均高于该标准.  相似文献   

8.
采用密胺包覆聚磷酸铵(APP)、季戊四醇(PER)和三聚氰胺(MEL)作为膨胀型阻燃剂(IFR)对不饱和树脂(UP)进行改性,研究了APP、PER和MEL不同复配比例及用量对不饱和树脂基复合材料阻燃性能和力学性能的影响。基于IFR最佳用量,以二乙基次磷酸铝(ADP)为协效剂,研究了ADP用量对IFR/UP阻燃复合材料阻燃性能、力学性能及热稳定性的影响。结果表明,当APP∶PER∶MEL复配比例为4∶1∶1,IFR添加量为15 %(质量分数,下同)时,复合材料综合性能最佳,其极限氧指数为27.4 %,UL 94垂直燃烧达到V?1等级,弯曲强度和冲击韧性分别为100.3 MPa和6.3 kJ/m2;ADP的引入能够进一步提高IFR/UP复合材料阻燃性能,且随着ADP质量分数的增加而增强;当ADP质量分数为2 %时,IFR?ADP/UP复合材料极限氧指数为28.5 %并达到V?0阻燃等级,弯曲强度和冲击韧性分别为110 MPa和7.8 kJ/m2,与IFR/UP复合材料相比,分别提高了9.7 %和23.8 %;ADP能够促进IFR/UP复合材料表面成炭,缓解基体的热降解。  相似文献   

9.
A simple approach was applied to probe into the situation of interfacial adhesion in the compatibilized ternary polymer blends with core/shell morphology. The performance of compatibilization was discussed in terms of thermal, rheological, and mechanical properties analyses for blends prepared through different mixing strategies for which maleic anhydride‐grafted high‐density polyethylene (HDPE‐g‐MAH) could be localized at the interface of HDPE/poly(ethylene‐co‐vinyl alcohol) copolymer (EVOH) or HDPE/polyamide 6 (PA‐6) in their ternary blends. Two mixing strategies, one simultaneously (one‐step or selective) and two sequentially (two‐step or dictated), were performed, compared, and discussed. It was found that mixing policy (dictated or selective) significantly changes the interfacial adhesion, as signaled by variations in rheological and thermal properties. In the case of mechanical properties, facilitation of stress transfer across the matrix/shell/core interfaces was detected by calculation of semi‐experimental models' coefficients. It was found that one‐step mixing or selective localization of HDPE‐g‐MAH helps in accumulation of more compatibilizer molecules at the interface HDPE/EVOH or EVOH/PA‐6. By contrast, addition of compatibilizer to minor phase (masterbatch of EVOH and PA‐6) or to HDPE matrix alone in case of two‐step blending causes imperfect stress transfer. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45503.  相似文献   

10.
针对三聚氰胺氰尿酸盐(MCA)粉体对尼龙(PA)进行阻燃改性时,MCA分散性差,材料阻燃性能不稳定的问题,运用特殊的包覆工艺成功制得了PA基MCA母粒。将制得的MCA母粒及MCA粉体分别与PA6或PA66共混挤出,制得阻燃PA材料。对比分析了MCA母粒及MCA粉体阻燃PA6或PA66的垂直燃烧性能和力学性能。结果表明,与MCA粉体相比,MCA母粒可在MCA含量较低的情况下使厚度为0.8 mm及1.6 mm的阻燃PA6或PA66试样的垂直燃烧等级达到V–0级。MCA母粒及粉体对阻燃PA6的弯曲强度和PA66的拉伸强度影响很小,MCA母粒阻燃PA6的拉伸强度较粉体阻燃的高,而阻燃PA66的弯曲强度低;MCA母粒使阻燃PA的缺口冲击强度降低,而MCA粉体对PA的缺口冲击强度影响较小,当MCA含量较低时,MCA母粒阻燃PA的缺口冲击强度明显高于MCA粉体阻燃的PA。制备的MCA阻燃母粒对PA的阻燃效果不受黑色母料的影响,且具有较好的阻燃稳定性。  相似文献   

11.
随着膨胀型阻燃剂(IFR)用量的增加,聚丙烯(PP)复合材料的冲击强度会不断降低。为提高PP/IFR复合材料的抗冲击韧性,使用了少量有机蒙脱土(OMMT)和聚烯烃弹性体(POE)协同增韧。结果表明,所制备的PP/IFR/POE/OMMT复合材料的极限氧指数最高为29.3%,达到UL94 V-0等级。当OMMT的质量分数为0.5%,POE质量分数为15%时,复合材料的冲击强度达到21.8 kJ/m~2,几乎是PP/IFR复合材料的6倍。此外,PP/IFR/POE/OMMT复合材料的熔体质量流动速率大于9.5 g/10min,具有良好的流动性。这种PP阻燃复合材料在汽车、家电、工业与民用建筑等领域具有广阔的应用前景。  相似文献   

12.
In this paper, a new bio-based flame retardant MHPA was prepared by the reaction of magnesium hydroxide (MH) and phytic acid (PA). Then the crosslinked high-density polyethylene (HDPE) flame-retardant composite was prepared by adding it and silicone rubber (SR) into HDPE and using electron beam irradiation. The test results of limiting oxygen index (LOI) and cone calorimeter test (CCT) show that the combination of MHPA and SR can increase the flame retardancy and smoke suppression performance of HDPE. The LOI of HDPE composite with 10 parts of SR is 28.3%, and its pHRR, THR and TSP values are reduced to 454.1 kW/m2, 99.7 MJ/m2 and 8.3 m2, respectively, which is because MHPA and SR jointly promote the formation of continuous and high-density carbon slag in the combustion process of HDPE and inhibit the penetration of flame. In addition, the HDPE composite with 10 parts of SR has significant tensile strength, elongation breaking strength and tear strength, because SR can produce continuous stable structure with HDPE after irradiation and crosslinking. Therefore, this study verified that MHPA and SR together can effectively improve the flame retardancy, smoke suppression and mechanical properties of HDPE composite.  相似文献   

13.
Synergistic flame‐retardant effect of halloysite nanotubes (HNTs) on an intumescent flame retardant (IFR) in low‐density polyethylene (LDPE) was investigated by limited oxygen index (LOI), vertical burning test (UL‐94), thermogravimetric analysis (TGA), cone calorimeter (CC) test, and scanning electronic microscopy (SEM). The results of LOI and UL‐94 tests indicated that the addition of HNTs could dramatically increase the LOI value of LDPE/IFR in the case that the mass ratio of HNTs to IFR was 2/28 at 30 wt % of total flame retardant. Moreover, in this case the prepared samples could pass the V‐0 rating in UL‐94 tests. CC tests results showed that, for LDPE/IFR, both the heat release rate and the total heat release significantly decreased because of the incorporation of 2 wt % of HNTs. SEM observations directly approved that HNTs could promote the formation of more continuous and compact intumescent char layer in LDPE/IFR. TGA results demonstrated that the residue of LDPE/IFR containing 2 wt % of HNTs was obviously more than that of LDPE/IFR at the same total flame retardant of 30 wt % at 700°C under an air atmosphere, and its maximum decomposing rate was also lower than that of LDPE/IFR, suggesting that HNTs facilitated the charring of LDPE/IFR and its thermal stability at high temperature in this case. Both TGA and SEM results interpreted the mechanism on the synergistic effect of HNTs on IFR in LDPE, which is that the migration of HNTs to the surface during the combustion process led to the formation of a more compact barrier, resulting in the promotion of flame retardancy of LDPE/IFR. In addition, the mechanical properties of LDPE/IFR/HNTs systems were studied, the results showed that the addition of 0.5–2 wt % of HNTs could increase the tensile strength and the elongation at break of LDPE/IFR simultaneously. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40065.  相似文献   

14.
罗兴  何敏 《塑料》2020,49(2):7-9,13
采用熔融共混技术制备了长玻璃纤维增强聚丙烯/膨胀阻燃剂/有机蒙脱土(LGFPP/IFR/OMMT)复合材料。利用极限氧指数(LOI)、锥形量热仪(CONE)以及万能力学试验机,表征了LGFPP/IFR/OMMT复合材料的阻燃性能、燃烧性能以及力学性能。氧指数测试结果表明,OMMT使LGFPP/IFR体系的氧指数提高。当添加2%OMMT时,LGFPP/IFR/OMMT复合材料的氧指数提高至24.2%。锥形量热仪测试结果表明,LGFPP/IFR体系的热释放速率峰值(PHRR)、烟雾生产率(THR)及引燃时间(TTI)均由于添加OMMT而大幅度降低。力学性能测试结果表明,LGFPP/IFR体系的拉伸强度、弯曲强度以及缺口冲击强度因OMMT的添加,分别提高了8.15%、9.04%和24%,使LGFPP/IFR体系中由于IFR引起LGFPP力学性能降低的弊端得到了明显改善。  相似文献   

15.
Poly(butylene terephthalate)/high density polyethylene (PBT/HDPE) blends and PBT/HDPE‐grafted maleic anhydride (PBT/HDPE‐g‐MAH) blends were prepared by the reactive extrusion approach, and the effect of blend compositions on the morphologies and properties of PBT/HDPE blends and PBT/HDPE‐g‐MAH blends was studied in detail. The results showed that flexural strength, tensile strength, and notched impact strength of PBT/HDPE blends decreased with the addition of HDPE, and flexural strength and tensile strength of PBT/HDPE‐g‐MAH blends decreased, while the notched impact strength of PBT/HDPE‐g‐MAH increased with the addition of HDPE‐g‐MAH. Compared with PBT/HDPE blends, the dimension of the dispersed phase particles in PBT/HDPE‐g‐MAH blends was decreased and the interfacial adhesion was increased. On the other hand, the effects of HDPE and HDPE‐g‐MAH contents on the crystalline and the rheological properties of the blends were also investigated. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 6081–6087, 2006  相似文献   

16.
In this research, we attempt to improve the impact strength and the viscosity of PA (polyamide) by blending two elastomers, TPU (thermoplastic polyurethane) and POE‐g‐MA (maleic anhydride‐grafted polyethylene‐octene elastomer), in PA matrix with twin screw extruder. The ratio of blending is 80PA/20TPU and 80PA/20TPU/20POE‐g‐MA (66.66PA/16.67TPU/16.67POE‐g‐MA). Results indicate that POE‐g‐MA improves the low viscosity of PA and TPU during the blending process, and also their compatibility. Thus, the 80PA/20TPU/20POE‐g‐MA blend has better tensile stress and elongation than 80PA/20TPU blend, and furthermore POE‐g‐MA significantly improves the impact strength of PA, even to super‐toughness grade. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

17.
膨胀阻燃剂在尼龙66中的应用   总被引:7,自引:0,他引:7  
在PA66/膨胀型阻燃剂(IFR)复合体系的阻燃机基础上,研究了PAD66/IFR体系的阻燃性,耐漏电性能。结果发现,IFR各组分间如果搭配得合理将具有明显的协同阻燃作用,但PA66/IFR材料的阻燃性和耐漏电性之间具有一定的矛盾性。  相似文献   

18.
The phosphoric acid‐pentaerythritol‐melamine copolymer, which is composed of three main components of intumescent flame retardant (IFR) and has optimal intumescent degree, was selected as IFR. The influence of meleated polypropylene (PP‐g‐MAH) on the properties and compatibility of IFR polypropylene (PP) composites were studied. The results obtained from mechanical tests, rheological behavior of composites, and scanning electron microscope showed that PP‐g‐MAH was a true coupling agent for IFR/PP blends and did not change the necessary flame retardancy. The cocrystallization between bulk PP and PP segments of PP‐g‐MAH was also proven by WAXD analysis. Flow test showed that the flow behaviors of composites in the melt are those of a pseudoplastic and it is very small for PP‐g‐MAH affecting rheological behavior of the PP/IFR composite. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 257–262, 2002  相似文献   

19.
The effect of polyethylene-grafted maleic anhydride (PE-g-MAH) on the tensile properties, morphology and thermal properties of low-density polyethylene (LDPE)/eggshell powder (ESP) composites was studied. LDPE/ESP composites with different eggshell powder content and the addition of PE-g-MAH were prepared with Z-blade mixer at 180°C and rotor speed of 50 rpm. The tensile strength, elongation at break and thermal stability of LDPE/ESP composites with PE-g-MAH were greater than LDPE/ESP composites, and their differences became more pronounced at higher filler content. The interfacial adhesion between ESP and LDPE was improved with the addition of PE-g-MAH as evidenced by the morphological study.  相似文献   

20.
A phosphoric acid–pentaerythritol–melamine copolymer was selected as an intumescent flame retardant (IFR). The influence of α‐methacrylic acid grafted polypropylene (PP‐g‐MAA) on the properties and compatibility of IFR/PP composites was studied. The results obtained from mechanical tests and scanning electron microscopy showed that PP‐g‐MAA was a true coupling agent for IFR/PP blends, but it did not change the necessary flame retardancy. The cocrystallization between bulk PP and PP segments of PP‐g‐MAA was proved by wide‐angle X‐ray diffraction analysis. A flow test showed that the flow behaviors of composites in the melt were those of a pseudoplastic liquid and it was very small for PP‐g‐MAA and affected the rheological behavior of the PP/IFR composite. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 3128–3132, 2002; DOI 10.1002/app.10099  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司    京ICP备09084417号-23

京公网安备 11010802026262号