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1.
In this study, nanosized clay particles were introduced into wood fiber/plastic composites (WPCs) to improve their mechanical properties and flame retardancy, which are especially important in various automotive and construction applications. A high degree of exfoliation for nanoclay in the wood fiber/high density polyethylene (HDPE) composites was successfully achieved with the aid of maleated HDPE (PE‐g‐MAn), through a melt blending masterbatch process. The structures and morphologies of the composites were determined using X‐ray diffraction (XRD) and transmission electron microscopy (TEM), respectively. This article presents the effects of clay content and degree of clay dispersion on the mechanical and physical properties and flame retardancy of wood fiber/HDPE composites that contained a small amount of clay, in the range of 3–5 wt %. We concluded that achieving a higher degree of dispersion for the nanosized clay particles is critical to enhance the mechanical properties and the flame retardancy of WPCs when small amounts of clay are used. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

2.
This work aimed to examine flame retardancy, antifungal performance and physical–mechanical properties for silane‐treated wood–polymer composites (WPCs) containing zinc borate (ZnB). ZnB with content from 0.0 to 7.0 wt% was added to WPCs, and silane‐treated wood contents were varied. The polymers used were poly(vinyl chloride) (PVC) and high‐density polyethylene (HDPE). The decay test was performed according to the European standard EN 113. Loweporus sp., a white‐rot fungus, was used for antifungal performance evaluation. Antifungal performance was observed to decrease with wood content. Incorporation of ZnB at 1.0 wt% significantly increased the antifungal performance of WPCs. ZnB content of greater than 1.0 wt% lowered the antifungal properties of WPCs. The results suggested that the wood/PVC composite exhibited better antifungal performance than the wood/HDPE composite. The addition of wood flour to PVC and HDPE decreased flame retardancy, whereas the incorporation of ZnB retained the flame retardancy. ZnB was found to be more appropriate for wood/PVC than wood/HDPE as a result of hydrogen chloride generated from the dehydrochlorination reaction of PVC. The results indicated that the addition of ZnB did not affect the physical‐mechanical properties of neat polymers and the composites. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

3.
Many authors have reported on the property enhancements possible by compounding high density polyethylene (HDPE) with fillers to produce composites. It is accepted that polyethylene combined with materials such as nanoclay or wood flour will not yield favorable properties unless a compatibilizing material is used to form a link. In this work, compatibilized HDPE was produced by grafting maleic anhydride (MA) to its backbone in a twin screw extruder using a peroxide initiated reactive process. Fourier transform infrared spectroscopy (FTIR) was used to examine the effects of varying peroxide and MA levels on the grafting percentage and it was found that a high percentage could be achieved. The gel content of each HDPE‐g‐MA batch was determined and twin bore rheometry analysis was carried out to examine the effects of crosslinking and MA grafting on the melt viscosity. These HDPE‐g‐MA compatibilizers were subsequently compounded with nanoclay and wood flour to produce composites. The composite materials were tested using a three point bending apparatus to determine the flexural modulus and strength and were shown to have favorable mechanical properties when compared with composites containing no compatibilizer. X‐ray diffraction (XRD) was used to examine the effects of grafted MA content on the intercalation and exfoliation levels of nanoclay composites. The results from XRD scans showed that increased intercalation in polymer nanoclay composites was achieved by increasing the grafted MA content. This was confirmed using a scanning electron microscope, where images produced showed increased levels of dispersion and reductions in nanoclay agglomerates. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

4.
The combination of a polyaminoamide‐epichlorohydrin (PAE) resin (a paper wet strength agent) and stearic anhydride was recently reported as an effective compatibilizer system for wood‐polyethylene composites. Further investigation of this new compatibilizer system revealed that the pH value of a PAE solution, dosages of PAE and stearic anhydride, and the weight ratio of PAE to stearic anhydride had significant impacts on the compatibilization effects of the compatibilizer system. Adjusting the pH value of the PAE solution from 5.0 to 10.4 increased the strength of the resulting wood‐polyethylene composites. The highest strength of the resulting wood‐polyethylene composites was obtained at 3 wt % PAE and 3 wt % stearic anhydride. At 4 wt % or 6 wt % of a compatibilizer, this PAE‐stearic anhydride system was superior to maleic anhydride‐grafted polyethylene (MAPE), one of the most effective compatibilizers, in terms of enhancing the strength of the resulting wood‐polyethylene composites. Fourier transform infrared spectroscopy (FTIR) analysis revealed that PAE and stearic anhydride formed covalent bonding with wood flour. The compatibilization mechanisms of this PAE‐stearic anhydride compatibilizer system were investigated in detail. Water‐resistance tests indicated that the PAE‐stearic anhydride compatibilizer system increased the water‐resistance of the resulting composites. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 712–718, 2006  相似文献   

5.
Epoxidized natural rubber (ENR) with a level of epoxide groups of 20 mol % was prepared via the performic epoxidation method. It was then used to blend with high‐density polyethylene (HDPE) at various blend ratios. Three types of blend compatibilizers were prepared. These included a graft copolymer of HDPE and maleic anhydride (MA; i.e., HDPE‐g‐MA) and two types of phenolic modified HDPEs using phenolic resins SP‐1045 and HRJ‐10518 (i.e., PhSP‐PE and PhHRJ‐PE), respectively. We found that the blend with compatibilizer exhibited superior tensile strength, hardness, and set properties to that of the blend without compatibilizer. The ENR and HDPE interaction via the link of compatibilizer molecules was the polar functional groups of the compatibilizer with the oxirane groups in the ENR molecules. Also, another end of the compatibilizer molecules (i.e., HDPE segments) was compatibilizing with the HDPE molecules in the blend components. The blend with compatibilizer also showed smaller phase morphology than the blend without compatibilizer. Among the three types of the blend compatibilizer, HDPE‐g‐MA provided the blend with the greatest strength and hardness properties but the lowest set properties. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

6.
The influence of 3‐(trimethoxysilyl)propyl methacrylate and benzoyl peroxide on gel content, crystallinity, and mechanical performance of unfilled PP‐PE blends, and their composites with wood was investigated. All materials were compounded in a twin screw extruder and then injection molded. Specimens were then exposed to high‐humidity and elevated temperature in a humidity chamber to cross‐link any unhydrolyzed silane. Adding wood to the PE‐PP blends, increased premature cross‐linking but also increased gel contents. However, the gel contents of the composites were still low. The PP component did not appear to cross‐link well and our gels were almost entirely HDPE. Fourier Transfer Infrared (FTIR) spectra provided additional evidence that TMSPM is grafted and cross‐linked in unfilled PE‐PP blends. Unfortunately, the spectra of wood composites proved difficult to interpret because of the complexity and overlap of the FTIR spectra of the wood. The HDPE component annealed when exposed to high‐humidity and elevated temperature, although less so in samples with high‐gel contents, presumably because of the decreased mobility. Annealing influenced mechanical performance, especially increasing moduli. Adding peroxide and silane appeared to improve adhesion between the wood flour and matrix in the composites but had little effect on energy absorbed during high‐speed puncture tests. Published 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

7.
The effect of surface modification on the mechanical properties and microstructure of the composites of high‐density polyethylene (HDPE), silicone oil, and aluminum hydroxide [Al(OH)3] was investigated. The dispersion of silicone oil in the HDPE composites was studied by scanning electric microscope (SEM) and differential scanning calorimetry (DSC). In the HDPE/Al(OH)3/silicone oil composites, two types of dispersion structure of silicone oil were observed resulting from different surface modifications. In the composites surface modified with titanate NDZ‐130, calcium stearate, or oleic acid, silicone oil encapsulates around Al(OH)3 particles, and both the notched impact strength and the elongation at break are very high. However, in the composites surface modified with silane KH‐550 or silane‐g‐HDPE, silicone oil and Al(OH)3 particles separately disperse in HDPE, and both the notched impact strength and the elongation at break are very low. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1896–1903, 2002  相似文献   

8.
In this study, rice‐straw (RS) filled high density polyethylene (HDPE) composites were manufactured by extrusion and injection molding. Three compatibilizers, which are unfunctionalized ethylene/propylene copolymer (uEPR), maleic anhydride grafted EPR (EPR‐g‐MA) and PE‐g‐MA, and their combinations were introduced to strengthen fiber‐matrix interphase. The mechanical and morphological properties of composites were investigated. For single‐compatibilizer system, PE‐g‐MA or EPR‐g‐MA alone enhanced tensile, flexural, and impact strengths of resultant composites compared with HDPE/RS system without compatibilizers. Different toughening origins of individual compatibilizer were discussed based on composites' interphase morphologies and mechanical properties. For combined‐compatibilizers system, the PE‐g‐MA/EPR weight ratio is important for several properties of composites. The optimum ratio was considered as 2 : 1 and 1 : 1 for PE‐g‐MA/uEPR and PE‐g‐MA/EPR‐g‐MA modified composites, respectively. Also, composites modified by combined PE‐g‐MA/EPR‐g‐MA showed better impact strength than that modified by PE‐g‐MA alone. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

9.
In the present work, different compatibilizers, namely polyethylene‐graft‐maleic anhydride (PE‐g‐MA), polypropylene‐graft‐maleic anhydride (PP‐g‐MA), and polystyrene‐block‐poly(ethylene‐ran‐butylene)‐block‐polystyrene‐graft‐maleic anhydride (SEBS‐g‐MA) were used on green composites derived from biobased polyethylene and peanut shell (PNS) flour to improve particle–polymer interaction. Composites of high‐density polyethylene/peanut shell powder (HDPE/PNS) with 10 wt % PNS flour were compatibilized with 3 wt % of the abovementioned compatibilizers. As per the results, PP‐g‐MA copolymer lead to best optimized properties as evidenced by mechanical characterization. In addition, best particle–matrix interface interactions with PP‐g‐MA were observed by scanning electron microscopy (SEM). Subsequently HDPE/PNS composites with varying PNS flour content in the 5–30 wt % range with PP‐g‐MA compatibilizer were obtained by melt extrusion and compounding followed by injection molding and were characterized by mechanical, thermal, and morphological techniques. The results showed that PNS powder, leads to an increase in mechanical resistant properties (mainly, flexural modulus, and strength) while a decrease in mechanical ductile properties, that is, elongation at break and impact absorbed energy is observed with increasing PNS flour content. Furthermore, PNS flour provides an increase in thermal stability due to the natural antioxidant properties of PNS. In particular, composites containing 30 wt % PNS powder present a flexural strength 24% and a flexural modulus 72% higher than the unfilled polyethylene and the thermo‐oxidative onset degradation temperature is increased from 232 °C up to 254 °C thus indicating a marked thermal stabilization effect. Resultant composites can show a great deal of potential as base materials for wood plastic composites. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43940.  相似文献   

10.
Shuai He  Ling Zhou  Hui He 《Polymer Composites》2015,36(12):2265-2274
In this research a type of wood plastic composites (TR‐WPCs) is prepared by blending tea residue (TR) with high‐density polyethylene (HDPE). The chemical composition of TR was analyzed quantitatively. The effects of TR content, compatibilizers, and nanofillers on the structure, morphology, and mechanical properties were studied. The results showed that the stiffness of TR‐WPCs was significantly improved with the increase in TR, while the strength and toughness decreased. Scanning electron microscope indicated that the maleic anhydride grafted polyethylene as compatibilizer enhanced interface adhesion of the composites; Thermo‐gravimetric analysis and Vicat test showed that the composite made with the nanofiller could improve the heat stability and heat resistance. Differential scanning calorimetry indicated that the addition of inorganic fillers slightly influenced the crystallization behavior of the HDPE matrix. The TR with boiling water treatment could significantly improve the mechanical properties of the composites. POLYM. COMPOS., 36:2265–2274, 2015. © 2014 Society of Plastics Engineers  相似文献   

11.
Nanoclay (NC) reinforced high‐density polyethylene (HDPE) composites were prepared by different melt compounding methods using (1) a single screw extruder (SSE), (2) twin screw extruder (TSE), (3) a combination of SSE and extensional flow mixer (EFM), and (4) a bowl mixer masterbatch method (MB). PE‐grafted maleic anhydride (PE‐g‐MA) was used as a compatibilizer. EFM increased complex melt viscosity (η*) of the HDPE/NC composites as compared to the neat HDPE and also provided a better interaction between HDPE and NC to create slightly lower melt η* as compared to MB and PE‐g‐MA composites. The low viscosity melt behavior of the pure HDPE changes to more solid like melt behavior in the PE‐g‐MA HDPE/NC composites in the low frequency (ω) region. PE‐g‐MA + EFM method exhibited better impact strength compared to the other HDPE/NC composites. Using the PE‐g‐MA and masterbatch compounding methods had a beneficial role in improving mechanical properties. POLYM. ENG. SCI., 57:324–334, 2017. © 2016 Society of Plastics Engineers  相似文献   

12.
Organically modified montmorillonite (org‐MMT) and high‐density polyethylene (HDPE) grafted with silane groups (HDPE‐g‐silane) were melt compounded to give HDPE‐g‐silane‐blend‐org‐MMT nanocomposites. X‐ray diffractometry was performed to investigate the intercalation effect. Transmission electron microscopy was applied to observe the dispersion of org‐MMT layers in HDPE matrices. The results indicate that an intercalated structure can be easily obtained in HDPE‐g‐silane‐blend‐org‐MMT nanocomposites. Furthermore, positron annihilation lifetime spectroscopy was used to characterize the microstructure of the composites. It is found that the ortho‐positron (o‐Ps) intensity for HDPE‐g‐silane is decreased by approximately 10% with a narrower lifetime distribution than that for HDPE. With increasing org‐MMT concentration, the o‐Ps intensity I3 increases for HDPE‐g‐silane‐blend‐org‐MMT nanocomposites; however, for HDPE‐blend‐org‐MMT composites I3 decreases. It is found that HDPE composites with good dispersion can be obtained following appropriate modification of the HDPE. And silane grafting has an effect on the free volume of the HDPE nanocomposites. Copyright © 2007 Society of Chemical Industry  相似文献   

13.
Effects of wood flour species and polyethylene grafted with maleic anhydride (MA‐PE) on mechanical properties and morphology and torque rheology of high density polyethylene (HDPE)/wood flour composites have been comparatively investigated. The results demonstrated that without compatbilizer, wood flour species exhibited little influence on mechanical properties. In the presence of MA‐PE, the mechanical properties were obviously increased. On the basis of the mechanical property data obtained from wood flour extracted by different methods, the extractant was an important factor affecting the mechanical properties. Manchurian ash and larch wood flours extracted by hot water presented almost the same mechanical properties, and larch wood flour was the most beneficial to enhance the mechanical properties. The scanning electron microscopy (SEM) and the atomic force microscopy (AFM) further confirmed that interfacial adhesion and dispersion of manchurian ash wood flour in composites were effectively improved by MA‐PE. The torque results demonstrated that the chemical reactions of maleic anhydride groups on MA‐PE with hydroxyl on cellulose in wood flour probably took place due to the increase of the equilibrium torque and the appearance of the torque peak, and larch wood flour was more beneficial to prepare the composites containing the higher wood flour content. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

14.
Silicone masterbatch (SMB) is a pelletized formulation containing 50% of an ultrahigh molecular‐weight polydimethylsiloxane dispersed in polyethylene. This SMB is designed to be used as an additive in polyethylene‐compatible systems to impart benefits such as processing improvement and modification of surface characteristics. In this work, binary blends of high‐density polyethylene (HDPE) and SMB were prepared by melt‐mixing technique to study the influence of this masterbatch on the processing and mechanical properties of HDPE. Ternary blends were also prepared by the addition of silane‐grafted polyethylene (HDPE‐VTES) as compatibilizer. The blends were analyzed by melting flow rate (MFR), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and tensile tests. Data of final torque and MFR showed that SMB improved the processability of pure HDPE. DSC results showed differences in crystalline behavior between binary and ternary blends. In the former, the degree of crystallinity increased up to 10 wt % of SMB content; beyond this concentration, it decreased. In ternary blends, a reverse behavior was observed. The morphologic study showed silicone particles uniformly distributed in HDPE matrix. With high SMB concentration, the addition of HDPE‐VTES significantly reduced the size of silicone particles. In the range of SMB composition studied, the mechanical properties of blends lower slightly compared to pure HDPE. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2347–2354, 2002  相似文献   

15.
A novel wood–plastic compatibilizer system containing a paper wet‐strength agent as a wood‐binding domain and stearic anhydride as a polyethylene (PE) binding domain was investigated. Treatment of wood flour with a commercial paper wet‐strength agent Kymene® 557H (simply called Kymene) before the mixing of PE and the wood flour increased the modulus of rupture (MOR) and the modulus of elasticity (MOE) of the resulting wood–PE composites. Addition of stearic acid in the mixing of PE and the wood–Kymene mixture further increased the MOR and MOE. Stearic anhydride was even more effective than stearic acid in the increase of the MOR and MOE. Compared to wood–PE composites without a compatibilizer, the stearic anhydride–Kymene compatibilizer system increased the MOR by about 33% and the MOE by about 40%. The stearic anhydride–Kymene compatibilizer system gave a slightly lower MOR, but higher MOE than those of the commercially used compatibilizer (maleic anhydride‐grafted polypropylene). The compatibilization mechanisms were proposed as follows: Kymene not only bound to wood fibers, but also strengthened and stiffened the wood fibers. Stearic anhydride formed covalent linkages such as ester and amide with the Kymene‐consolidated wood fibers and the long hydrocarbon chain of the stearic anhydride bonded to the PE matrix through entanglements and/or cocrystallization. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91: 3667–3672, 2004  相似文献   

16.
High‐density polyethylene/wood flour (HDPE/WF) composites were prepared by a twin‐screw extruder. The effects of WF, silane coupling agents, polymer compatibilizers, and their content on the comprehensive properties of the WF/HDPE composites have been studied in detail, including the mechanical, thermal, and rheological properties and microstructure. The results showed that both silane coupling agents and polymer compatibilizers could improve the interfacial adhesion between WF and HDPE, and further improve the properties of WF/HDPE composites, especially with AX8900 as a compatibilizer giving higher impact strength, and with HDPE‐g‐MAH as a compatibilizer giving the best tensile and flexural properties. The resultant composite has higher strength (tensile strength = 51.03 MPa) and better heat deflection temperature (63.1°C). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

17.
In this work, high‐density polyethylene (HDPE)‐based nanocomposites having different concentrations of Sepiolite (1–10 wt %) and compatibilizer, that is, PE‐graft‐maleic anhydride (PE‐g‐MA) of varying molecular weight and maleic anhydride content were prepared by melt compounding. The influence of Sepiolite amount and compatibilizer polarity and molar mass on the crystallization behavior [differential scanning calorimeter (DSC) and X‐ray diffraction (XRD)], rheological properties (oscillatory rheometer) and dimensional stability [dynamic mechanical analyzer (DMA) and heat deflection temperature (HDT)] of the nanocomposites was investigated. It was found that Sepiolite did not affect the crystallization behavior of HDPE. The rheological results show that the incorporation of Sepiolite into HDPE matrix up to 10 wt % increases the complex viscosity of polymer. Storage modulus and loss modulus both in oscillatory rheometry and in DMA were highest for nanocomposite prepared using 10 wt % Sepiolite owing to the improved mechanical restrain by the dispersed phase. In the presence of compatibilizer, the values of storage modulus and loss modulus were lower as compared to uncompatibilized nanocomposites at same loading of Sepiolite. The reduction in modulus is more pronounced in composites prepared using compatibilizer of lower molar mass as compared to those prepared using higher molar mass compatibilizer. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45197.  相似文献   

18.
In this study, the effect of oil fly ash (OFA), a by‐product of oil fuel power plants, on the rheological and morphological behavior of low‐density polyethylene (LDPE) is investigated. As received and acid‐functionalized OFA (COOH‐OFA) are used to examine the effect of surface modification of OFA on polymer–filler composites. LDPE/OFA composites were prepared by melt mixing with filler loading in the range 1–10 wt %. The results are compared with pure LDPE. The effect of polyethylene‐grafted‐maleic anhydride (PE‐g‐MA) as a compatibilizer was also studied. Both viscous and elastic properties of composites increased with OFA loading especially at low frequency. The surface modification of OFA has influenced the properties of OFA. As‐received OFA showed some agglomeration at high loading that resulted in two‐phase system as described by scanning electron microscopy (SEM) and Cole–Cole plot. Field emission‐SEM (FE‐SEM) images showed improvement in the dispersion of COOH‐LDPE/OFA composites. In addition, the surface modification reduced the size of agglomeration. In general, the COOH modification of OFA improved both the dispersion and rheological properties of OFA. With chemical modification, the concentration of the filler can be increased to 10% without compromising the properties of the composites. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.  相似文献   

19.
In this study, the influence of coupling agent concentration (0 and 3 wt%), wood fiber content (50, 60, 70, and 80 wt%), and size (40–60, 80–100, and 160–180 mesh) on the mechanical properties of wood/high-density-polyethylene (HDPE) composites (WPCs) was investigated. WPC samples were prepared with poplar wood-flour, HDPE, and polyethylene maleic anhydride copolymer (MAPE) as coupling agent. It was found that the tensile properties and the flexural properties of the composites were improved by the addition of 3 wt% MAPE, and the improved interfacial adhesion was well confirmed by SEM micrographs. It was also observed that the best mechanical properties of wood/HDPE composites can be reached with larger particle size in the range studied, while too-small particle size was adverse for the mechanical properties of wood/HDPE composites. Moreover, the tensile modulus, tensile strength, and flexural strength of WPCs decreased with the increase in fiber content from 50 to 80 wt%; the flexural modulus of WPCs increased with the increase in fiber content from 50 to 70 wt% and then decreased as the fiber content reached 80 wt%. The variances in property performance are helpful for the end-user to choose an appropriate coupling agent (MAPE) concentration, wood fiber content, and particle size based on performance needs and cost considerations.  相似文献   

20.
High density polyethylene/organo‐modified montmorillonite composites whit various concentrations of maleic anhydride grafted high density polyethylene (MA‐g‐HDPE) as compatibilizer (5–20 wt %) have been prepared by melt process. The extruded composite powders are applied on the treated steel surfaces using spray electrostatic powder technique, followed by oven curing at various temperatures (180°C–220°C) and times (15–45 min). The surface uniformity of produced coating films is studied by scanning electron microscopy. Comparison of micrographs of the coatings shows the composite coating films are measured using standard methods. The uniformity, adhesion, and bending strength of the coating films are compared to select high performance coatings. The results indicate that the presence of 15 wt % MA‐g‐HDPE in the coatings shows the highest properties (adhesion and bending strength) and more surface uniformity. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40926.  相似文献   

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