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1.
Differential scanning calorimetry has been used to study the heat flow during melting and crystallisation of a range of polypropylene post-consumer waste (PP PCW) grades and blends. The heat flow curves and the heat capacity curves indicated that the PP PCW grades and blends contained contaminants even after manual sorting and a cleaning process. The enthalpies of the PP PCW grades were lower than that for the virgin grades, as a result of degradation. Small amounts of polymeric contaminants (up to 10%) did not affect the enthalpies of PP PCW although other contaminants may have had some effect. The enthalpies of the PCW blends could in general be predicted by a linear additive rule, which is of importance for recycling a variety of PP PCW products.The authors would like to thank Dr. M. Killen (Basell Australia Pty. Ltd.), Mr. P. Slaven (Citiwide MRF), Dasma Valley Waste Prop. Ltd. and Mr. I. Janetzki (Huhtamaki Australia Ltd.) for supplying materials for this project. Financial support for the project was provided by Basell Australia and Ecorecycle Victoria, Australia.  相似文献   

2.
The mechanical and morphological characteristics of PA6/ABS (60/40)-based hybrid composite containing HNO3-treated short carbon fibers (HSCF) and CaCO3 nanoparticles have been experimentally studied. A counter-rotating twin-screw extruder and an injection molding machine were employed to produce different samples containing 10 wt % of HSCF and 0, 2, 5 and 8 wt % of CaCO3 nanoparticles. The SEM observations indicated high-quality adhesion between HNO3-surface treated carbon fibers and PA6/ABS polymer matrix. In addition, the morphological studies showed that the inclusion of CaCO3 nanoparticles caused a significant effect on the ABS particle dispersion in PA6/ABS matrix. The mechanical properties assessments revealed that the incorporation of 10 wt % HSCF into the PA6/ABS can significantly improve tensile strength (82%), tensile modulus (107%), flexural strength (98%), flexural modulus (104%) and impact resistance (24%). The inclusion of CaCO3 nanoparticles, in the presence of 10 wt % HSCF, led to the noticeable improvements of tensile strength (128% for 2 wt % CaCO3), tensile modulus (199% for 5 wt % CaCO3), flexural strength (146% for 5 wt % CaCO3), flexural modulus (204% for 5 wt % CaCO3) and impact resistance (46% for 2 wt % CaCO3). The surface treatment of carbon fibers, dispersion conditions of nanoparticles and ABS phase in polymeric matrix were found to be the major important factors affecting the mechanical properties.  相似文献   

3.
The impact of recycling by grinding and re-extrusion on the physical and mechanical properties of polypropylene (PP)/ethylene octene copolymer (EOC) blends was investigated. The considered EOC content was 0 wt. %, 10 wt. % and 20 wt. %, and the investigated number of recycling passes (extrusions) was 0, 1, 3 and 6. Up to 6 re-extrusions, an increase of the melt flow index (MFI), a slight increase of the crystallinity, a slight decrease of the decomposition temperature (Tonset), and no significant oxidation were noted. Therefore, the recycling of the blends induces thermomechanical degradation by chain scission without oxidation. Increasing the content of EOC increases the MFI and the Tonset of the PP blends. The first recycling procedure induced an increase of the Young's modulus and tensile yield stress, while for higher recycling numbers, these two parameters dropped. The EOC inclusions stabilized the tensile elongation at break up to 3 recycling procedures due to a decrease of their size and a homogenization of their shape, while that of neat PP continuously decreased with recycling numbers.  相似文献   

4.
A series of polyamide 6/polypropylene (PA6/PP) blends and nanocomposites containing 4 wt% of organophilic modified montmorillonite (MMT) were designed and prepared by melt compounding followed by injection molding. Maleic anhydride polyethylene octene elastomer (POEgMAH) was used as impact modifier as well as compatibilizer in the blend system. Three weight ratios of PA6/PP blends were prepared i.e. 80:20, 70:30, and 60:40. The mechanical properties of PA6/PP blends and nanocomposite were studied through flexural and impact properties. Scanning electron microscopy (SEM) was used to study the microstructure. The incorporation of 10 wt% POEgMAH into PA6/PP blends significantly increased the toughness with a corresponding reduction in strength and stiffness. However, on further addition of 4 wt% organoclay, the strength and modulus increased but with a sacrifice in impact strength. It was also found that the mechanical properties are a function of blend ratio with 70:30 PA6/PP having the highest impact strength, both for blends and nanocomposites. The morphological study revealed that within the blend ratio studied, the higher the PA6 content, the finer were the POEgMAH particles.  相似文献   

5.
用扫描电子显微镜图像分析研究了聚丙烯/聚酰胺1010共混物及其部分相容体系的相形态结构,计算了表征相结构和尺寸的结构参数,如分散相的平均直径、平均弦长和分散相的质心相关距等.并分别讨论了聚丙烯/聚酰胺1010共混物及其部分相容体系的相形态以及其结构参数与共混物组成的关系.测定了聚合物及其共混物体系的力学性能,讨论了共混物组成与力学性能的关系.聚丙烯/聚酰胺1010共混物的拉伸模量与组成的关系较为复杂,但其部分相容体系的拉伸模量与组成呈线性关系.聚丙烯/聚酰胺1010及其共混物体系的屈服强度与共混物组成均呈线性关系.表征相结构的两相平均弦长比(l-1/-l2)与组成以及共混物体系力学性能与组成的关系,二者相似.同时讨论了体系力学性能随相尺寸等的变化规律.  相似文献   

6.
超细聚酰胺6粒子增韧聚丙烯体系的研究   总被引:7,自引:0,他引:7  
陈哲  王琪  徐僖 《高分子学报》2001,37(1):13-16
采用磨盘形力化学反应器室温下制备了聚丙烯 (PP) /聚酰胺 6 (PA6 )超细粉体 ,研究了其粒度、粒度分布及PA6超细粒子填充对PP力学性能的影响 .结果表明 ,磨盘形力化学反应器可有效实现PP/PA6的粉碎 ,所得粉体平均粒径达微米级 ,初级粒子尺寸甚至可达纳米级 ,粒度分布呈双峰分布状态 .在PA6和PP熔点之间的温度下加工可制得PA6超细粒于填充的PP/PA6共混体系 ,其力学性能明显好于PP/PA6简单共混体系 ,30 %PA6用量下 ,拉伸强度由 2 3 .2MPa提高至 2 9 3MPa ,Izod缺口冲击强度由 4.6 2kJ/m2 提高到6 .34kJ/m2 .形貌分析结果表明 ,由于基本保持了PA6超细粉体的原始尺寸 ,填充体系中PA6相区尺寸小、分布均匀 ,与使用增容剂得到的相区结构类似 .  相似文献   

7.
PP-g-(GMA-co-St)对PA6/PC共混物的反应增容作用   总被引:10,自引:0,他引:10  
用红外、扫描电镜、熔体流动速率和力学性能等测试方法,研究了甲基丙烯酸缩水甘油酯(GMA)和苯乙烯(St)多单体熔融接枝聚丙烯[PP-g-(GMA-co-St)]对PA6/PC共混物的反应增容作用.研究结果表明,在熔融共混过程中,PP-g-(GMA-co-St)中的环氧基与PA6的端氨基及PC的端羟基原位生成的接枝共聚物有效地降低了共混物相间的界面张力,明显提高了共混物相界面的粘着力.少量的PP-g-(GMA-co-St)就能使PA6和PC的相容性得到显著改善.当PP-g-(GMA-co-St)的质量分数为10%时,共混物分散相的相区尺寸细化到0.2μm,其力学性能也有较大提高.PA6/PC/PP-g-(GMA-co-St)共混物的力学性能均衡,达到了弹性体增韧体系难以达到的效果.即使PP-g-(GMA-co-St)组分含量为20%时,共混物仍能保持较好的力学性能,特别是在共混物的韧性得以提高的同时,其强度和伸长率也提高.  相似文献   

8.
Polyamide 6/polypropylene (PA6/PP = 70/30 parts) blends containing 4 phr (parts per hundred resin) of organophilic modified montmorillonite (organoclay) were compatibilized with maleic anhydride-grafted ethylene-propylene rubber (EPRgMA). The blends were melt compounded in twin screw extruder followed by injection molding. The mechanical properties of PA6/PP nanocomposites were studied by tensile and flexural tests. The microstructure of the nanocomposite were assessed by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). The dynamic mechanical properties of the PA6/PP blend-based nanocomposites were analyzed by using a dynamic mechanical thermal analyzer (DMTA). The rheological properties were conducted from plate/plate rheometry via dynamic frequency sweep scans. The melt viscosity in a high shear rate region was performed by using a capillary rheometer. The strength and stiffness of the PA6/PP-based nanocomposites were improved significantly with the incorporation of EPRgMA. Adding EPRgMA to the PA6/PP blends resulted in a finer dispersion of the PP phase. TEM and XRD results revealed that the organoclay was dispersed more homogeneously in the presence of EPRgMA, however, mostly in the PA6 phase of the blends. DMTA results showed that EPRgMA worked as an effective compatibilizer. The storage (G′) and loss moduli (G″) assessed by plate/plate rheometry of PA6/PP blends increased with the incorporation of EPRgMA and organoclay. Furthermore, the apparent shear viscosity of the PA6/PP blend increased significantly for the EPRgMA compatibilized PA6/PP/organoclay nanocomposite. This was traced to the formation of an interphase between PA6 and PP (via PA6-g-EPR) and effective intercalation/exfoliation of the organoclay.  相似文献   

9.
The effect of functionalized multiwalled carbon nanotubes (FMWCNTs) on the phase morphology of immiscible high density polyethylene/polyamide 6 (HDPE/PA6, 50/50) blend has been investigated. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were employed to study both the morphology variation of the nanocomposites and the selective distribution of FMWCNTs in the nanocomposites. It is clear that adding small amount of FMWCNTs (<2.0 wt.%) does not exert profound influence on the sea-island morphology of the nanocomposites. However, at moderate content of FMWCNTs (2.0 and 5.0 wt.%), a typical cocontinuous morphology is detected. Further increasing FMWCNTs content (10.0 wt.%) induces phase inversion. The crystallization behaviors of both HDPE and PA6 components were investigated by using differential scanning calorimetry (DSC) and wide angle X-ray diffraction (WAXD). The results show the apparent nucleation effect of FMWCNTs for PA6 crystallization due to the selective distribution of FMWCNTs in PA6 phase. Rheological measurements exhibit the presence of FMWCNTs network structure in the nanocomposites. It is suggested that the formation of the cocontinuous morphology and the novel crystallization behaviors of PA6 at high content of FMWCNTs are ascribed to the formation of the FMWCNTs network structure.  相似文献   

10.
in situ Fibril formation of polyamide-6(PA6)in isotropic polypropylene(iPP)was first fabricated using a slit die extrusion and hot stretching process.Then the prepared materials were subjected to injection molding in the temperature range higher than the melting temperature of iPP but lower than that of PA6.The obtained injection-molded samples were characterized via scanning electron microscopy(SEM),differential scanning calorimetry(DSC)and two-dimensional wide- angle X-ray scattering(2D-WAXS).Mechanical properties were also investigated.The SEM result shows that the optimum fibril formation could be only achieved in the range of 20 wt% to 30 wt% of PA6 content for the studied system.The fibril morphology changes along the sample thickness in the injection-molded bars.The fibril morphology in the skin layer was better than that in the core layer.2D-WAXS results showed that the orientation of PP decreased with the increase of PA6 content,which indicated that the orientation of PP was confined by PA6 fibrils.Combined consideration of mechanical properties and morphology indicates that only PP/PA6 composites with 20 wt% of PA6 content show better properties because of the better fibril morphology and PP chain orientation.  相似文献   

11.
Polyamide 6/polypropylene (PA6/PP = 70/30 parts) blends containing 4 phr (parts per hundred resin) of organically modified clay (organoclay) toughened with maleated styrene-ethylene-butylene-styrene (SEBS-g-MA) were prepared by melt compounding using co-rotating twin-screw extruder followed by injection molding. X-ray diffraction (XRD) and transmission electron microscope (TEM) were used to characterize the structure of the nanocomposites. The mechanical properties of the nanocomposites were determined by tensile, flexural, and notched Izod impact tests. The single edge notch three point bending test was used to evaluate the fracture toughness of SEBS-g-MA toughened PA6/PP nanocomposites. Thermal properties were studied by using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). XRD and TEM results indicated the formation of the exfoliated structure for the PA6/PP/organoclay nanocomposites with and without SEBS-g-MA. With the exception of stiffness and strength, the addition of SEBS-g-MA into the PA6/PP/organoclay nanocomposites increased ductility, impact strength and fracture toughness. The elongation at break and fracture toughness of PA6/PP blends and nanocomposites were increased with increasing the testing speed, whereas tensile strength was decreased. The increase in ductility and fracture toughness at high testing speed could be attributed to the thermal blunting mechanism in front of crack tip. DSC results revealed that the presence of SEBS-g-MA had negligible effect on the melting and crystallization behavior of the PA6/PP/organoclay nanocomposites. TGA results showed that the incorporation of SEBS-g-MA increased the thermal stability of the nanocomposite.  相似文献   

12.
The effects of maleated thermoplastic elastomer (TPEg) on morphological development of polypropylene (PP)/polyamide 6 (PA6) blends with a fixed PA6 content (30 wt %) were investigated. For purpose of comparison, nonmaleated thermoplastic elastomer (TPE) was also added to the above binary blends. A comparative study of FTIR spectroscopy in above both ternary blends confirmed the formation of in situ graft copolymer in the PP/PA6/TPEg blend. Dynamic mechanical analysis (DMA) indicated that un‐like TPE, the incorporation of TPEg remarkably affected both intensity and position of loss peaks of blend components. Scanning electron microscopy (SEM) demonstrated that PP/PA6/TPE blends still exhibited poor interfacial adhesion between the dispersed phase and matrix. However, the use of TPEg induced a finer dispersion and promoted interfacial adhesion. Transmission electron microscopy (TEM) for PP/PA6/TPEg blends showed that a core‐shell structure consisting of PA6 particles encapsulated by an interlayer was formed in PP matrix. With the concentration of TPEg increasing, the dispersed core‐shell particles morphology was found to transform from discrete acorn‐type particles to agglomerate with increasing degree of encapsulation. The modified Harkin's equation was applied to illustrate the evolution of morphology with TPEg concentration. “Droplet‐sandwiched experiments” further confirmed the encapsulation morphology in PP/PA6/TPEg blends. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 1050–1061, 2006  相似文献   

13.
The structure and mechanical properties of injection‐molded bars of high‐density polyethylene (HDPE)/PA6 blends were studied in this article. The experimental results showed that the morphologies of injection‐molded bars change gradually along the flow direction, which is tightly related to the melt viscosity and processing conditions. The higher melt viscosity, lower mold temperature, and shorter packing time, restricting the macromolecular relaxation, enhance the difference in morphologies and properties at near and far parts of a mold. An injection‐molded bar (namely H2C5), consisting of 75 wt % of HDPE, 20 wt % of PA6, and 5 wt % of compatibilizer (HDPE‐g‐MAH), showed a greater difference in mechanical properties at near and far parts because of its higher melt viscosity. A clear interface between the skin and core layers of near part in it leads to a much higher impact strength than that of far part. And tensile tests show that its tensile strength of near part is higher than that of far part due to the higher orientation degrees of HDPE matrix and PA6 dispersed phase in near part. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 184–195, 2007  相似文献   

14.
Samples of polyurethane nanocomposites were synthesized using diphenylmethane diisocyanate, poly(ε‐caprolactone) diol, di(ethylene glycol), and a clay functionalized by hydroxyl groups. The inorganic content in the hybrids was 2 wt %, 4 wt %, and 8 wt %. The X‐ray analysis showed that exfoliation occurred for clay content equal to 2% (w/w), whereas for higher contents, the inorganic phase rearranges in an intercalated structure. FTIR analysis suggested that the degree of hydrogen bonding in the hard segments was greatly reduced because of the amount of silicate layers and their dispersion. The dynamic‐mechanical analysis showed that the presence of clay lamellae extends very much the temperature range before the hard domain transition, causing the loss of mechanical consistency of the samples. It is less than 100 °C for the pure polymer, and increases up to 200 °C for the nanocomposites. The permeability of water vapor decreases linearly with inorganic content up to 4% of inorganic phase, and levels off at higher concentrations. The permeability behavior, at low activities, is largely dominated by the diffusion phenomenon. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 2454–2467, 2005  相似文献   

15.
Flame‐retardant polyamide 6 (PA6) was prepared by an inorganic‐organic composite (MCN or MgO/g‐C3N4) synthesized by incorporating magnesium oxide (MgO) combined with graphitic carbon nitride (g‐C3N4). As compared to g‐C3N4, MCN possessed a laminate structure, more holes, and a larger specific surface area. The addition of MCN could effectively improve the flame retardancy and mechanical properties of PA6 due to its better compatibility and dispersion in the PA6 matrix. When the addition of MCN was 20 wt%, the vertical combustion performance of the PA6/MCN sample reached flammability rating V‐0 (UL‐94) and the limiting oxygen index (LOI) was up to 32.1%. The results of thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) revealed that the introduction of MCN efficiently enhanced thermal stability of PA6. The morphologies of the char residue observed by scanning electron microscopy (SEM) verified that MCN promoted the formation of sufficient, compact, and homogeneous char layers on the composite's surface during burning. Thus led to increase the char layer strength and improve the flame retardancy of PA6. The thermogravimetric analysis/infrared (TG‐IR) revealed the gas‐phase retardancy mechanism of MCN. Compared with PA6/g‐C3N4, PA6/MCN showed better mechanical properties in terms of flexural strength and tensile strength.  相似文献   

16.
Syndiotactic polystyrene (sPS) and polyamide-6 (PA6) are immiscible and incompatible and have been recognized. In this study, sulfonated syndiotactic polystyrene (SsPS-H) is employed as compatibilizer in the blend of sPS/PA6. During melt blending, the sulfonic acid groups of the SsPS-H can interact strongly with the amine end-groups of PA6 through acid-base interaction. In addition, SsPS-H is miscible with sPS when SsPS-H content is less than 20 wt.%. Therefore, the addition of SsPS-H to sPS/PA6 blends reduces the dispersed phase size and improves the adhesion between the phases. The glass transition temperatures of the PA6 component in the compatibilized blends shift progressively towards higher temperature with the content of SsPS-H-12 increase, indicating enhanced compatibility. On the other hand, the progressive lowering of the melting point and crystallization temperatures of PA6 in the blends with increasing SsPS-H contents compared to the incompatibilized blend, provide some insight into the level of interaction between the PA6 and SsPS-H. The compatibilized blends have significantly higher impact strength than the blends without SsPS-H. The best improvement in the impact strength of the blends was achieved with the content of the SsPS-H (11.9 mol%) about 5 wt.%.  相似文献   

17.
The viscoelastic behavior of multiwall carbon nanotube (MWCNT) reinforced polyamide 66 (PA 66) was evaluated to investigate the effect of CNT content and loading frequency on dynamic moduli (i.e. storage modulus E′ and loss modulus E″) and damping factor tanδ. PA 66/CNT disk samples with five different CNT contents ranging from 3 wt % to 15 wt % were manufactured by injection molding. Testing was performed over the frequency range of 0.1–100 Hz at room temperature. Dynamic mechanical analysis results show that the mechanical properties are highly functions of tested frequency and the improvement on loss and storage modulus of nanocomposites with the addition of CNT is highly dependent on tested frequencies. The variability in loss modulus is significantly higher than the variability in the storage modulus indicating the correlation of loss modulus with uncertainties present in nanocomposite microstructure while storage modulus is essentially independent of microstructure for a given reinforcement content.  相似文献   

18.
采用磨盘形力化学反应器,在室温下制备了PA6/PP超细混合粉体,与SBS共混制得PA6/PP/SBS共混物,测定了材料的力学性能并用TEM研究了材料在不同加工温度下相结构的变化.结果表明,通过固相力化学粉碎制备的PA6/PP混合微粉,改善了PA6与PP和SBS的相容性,促进了PA6及PP的分散和与SBS的相界面结合.在微粉填充量为4%~8%(质量分数)时,材料的拉伸强度大幅度提高,扯断伸长率保持不变.加工温度变化引起材料相结构的变化对材料性能产生显著影响.在PP熔融温度下加工,PP粒子产生粘连形成链状结构,可提高材料的力学性能.  相似文献   

19.
Polyamide 6 (PA6) solutions in formic acid (FA) and deionized water cosolvent may behave as polyelectrolyte or neutral solutions depending on the cosolvent composition. In this study, both polyelectrolyte and neutral PA6 solutions were prepared for electrospinning, and their spinnability was correlated with their rheological properties. In addition, the effects of PA6 average molecular weight and carbon nanocapsule (CNC) nanoparticle addition on solution rheology and electrospinnability were investigated. Microstructure and thermal properties of the as-spun fibers were identified by wide-angle X-ray diffraction, polarized Fourier infrared spectroscopy, and differential scanning calorimetry (DSC). Due to the chain expansion, polyelectrolyte solutions with 99 vol.% FA solvent possess much lower entanglement concentration (?e, ∼1 wt.%) than neutral solutions (∼7 wt.%) prepared by 90 and 85 vol.% FA solvent. Compared with the neutral solution, the polyelectrolyte solution is more advantageous because a lower concentration is sufficient to obtain bead-free PA6 fibers. However, at a concentrated regime of 15 wt.% solution, the obtained fibers exhibit a larger diameter due to the higher entanglement density. For the crystalline structure, the content and orientation of α-form crystals are higher in the PA6 fibers obtained from the polyelectrolyte than from the neutral solution. When PA6 with a lower molecular weight is used, a higher concentration is required to develop the entangled chains to produce bead-free fibers. Homogeneous PA6 solutions filled with CNCs exhibit more elastic behavior than unfilled solutions due to the presence of the CNC–CNC network, aside from the entangled network of PA6 chains. Electrospinning of the CNC-filled solutions yields PA6 fibers with CNC aggregates protruding from the fiber surface. The inclusion of CNC in the PA6/FA solution produces fibers possessing enhanced α-form crystals with reduced orientation. In all cases, DSC heating traces of the as-spun fibers identify a high melting temperature (HMT) phase of PA6. The amount of HMT phase decreases, provided that more water or CNCs are added into the PA6/FA solution for electrospinning.  相似文献   

20.
PA6/HIPS/PP-g-(GMA-co-St)反应共混体系的研究   总被引:7,自引:0,他引:7  
通过扫描电镜、热分析、熔体流动速率、熔融扭矩和力学性能等测试方法研究了甲基丙烯酸缩水甘油酯(GMA)和苯乙烯(St)多单体熔融接枝聚丙烯[PP-g-(GMA-co-St)]对PA6/HIPS共混物的熔融流变性能、结晶行为、相形态和力学性能的影响.结果表明,在熔融共混过程中,PP-g-(GMA-co-St)中的环氧基与PA6的端氨基原位生成的接枝共聚物有效地降低了共混物的界面张力,提高了共混物的界面粘着力,使共聚物的流动速率降低,熔融扭矩提高;PA6分子链的规整性降低,结晶完善性变差.在PP-g-(GMA-co-St)的质量分数为10%时,共混物分散相的尺寸明显减少,力学性能得到较大提高;其中冲击强度超过纯PA6,达到HIPS水平.通过反应共混,制备了力学性能均衡的PA6/HIPS/PP-g-(GMA-co-St)共混物合金.  相似文献   

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