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1.
BisGMA (Bisphenol-A-glycidyldimethacrylate) resin had been modified by incorporating TiO2 nanoparticles (0.5–2% by weight). An ultrasonic mixing process was used to disperse the particles into the resin system prior to casting and curing test specimens. TEM investigation showed that the particles were nano size (5–60 nm) and dispersed throughout the entire volume of the resin. In dynamic mechanical analysis, nanophase resin showed increase in storage modulus and glass transition temperature from neat resin system. Thermogravimetric analysis revealed better thermal stability. Flexural loading, T g and flexural modulus of the nanocomposites were enhanced as the particle volume fraction was enhanced and than decreased.  相似文献   

2.
Different proportions of nanoscale TiO2 (nano‐TiO2)‐filled polybutylene succinate (PBS) composites were prepared by vane extruder. The crystalline, thermal, dynamic viscoelastic, mechanical, and UV‐resistance properties of the composites were studied, and X‐ray diffraction, differential scanning calorimetry, and thermogravimetric analysis were conducted. Results show that the crystalline structure of the PBS composites did not change with TiO2 addition. TiO2 almost has no effect on the crystallization and melting behavior of PBS. Nevertheless, the introduction of TiO2 has improved the thermal stability, tensile modulus, flexural modulus, and flexural strength of the PBS composites. The UV resistance of the composites has also been significantly enhanced with TiO2 addition. POLYM. COMPOS., 35:53–59, 2014. © 2013 Society of Plastics Engineers  相似文献   

3.
In this study, the effects of multi‐walled carbon nanotubes (MWCNT), and its hybrids with iron oxide (Fe2O3) and copper oxide (CuO) nanoparticles on mechanical characteristics and thermal properties of epoxy binder was evaluated. Furthermore, simultaneous effects of using MWCNT with TiO2 as pigment and CaCO3 as filler for epoxy composites were determined. To investigate effects of nano‐ and micro‐particles on epoxy matrix, the samples were evaluated by TGA and DTA. It was found that the hybrid of MWCNT with nano metal oxides caused considerable increment in the tensile and flexural properties of epoxy samples in comparison to the single MWCNT containing samples at the same filler contents. Significant improvement in the thermal conductivity of epoxy samples was obtained by using TiO2 pigment along with MWCNT. The TiO2 pigment also caused considerable improvement in mechanical properties of the epoxy matrix and the MWCNT containing nanocomposite. The best mechanical and thermal properties of epoxy nanocomposites were obtained at 1.5 wt % of MWCNT and 7 wt % of TiO2 that it should be attributed to particle network forming of the particles which cause better nano/micro dispersion and properties. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43834.  相似文献   

4.
Poly (acrylonitrile‐butadiene‐styrene) (ABS) was used to modify diglycidyl ether of bisphenol‐A type of epoxy resin, and the modified epoxy resin was used as the matrix for making TiO2 reinforced nanocomposites and were cured with diaminodiphenyl sulfone for superior mechanical and thermal properties. The hybrid nanocomposites were characterized by using thermogravimetric analyzer (TGA), dynamic mechanical analyzer (DMA), universal testing machine (UTM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The bulk morphology was carefully analyzed by SEM and TEM and was supported by other techniques. DMA studies revealed that the DDS‐cured epoxy/ABS/TiO2 hybrid composites systems have two Tgs corresponding to epoxy and ABS rich phases and have better load bearing capacity with the addition of TiO2 particles. The addition of TiO2 induces a significant increase in tensile properties, impact strength, and fracture toughness with respect to neat blend matrix. Tensile toughness reveals a twofold increase with the addition of 0.7 wt % TiO2 filler in the blend matrix with respect to neat blend. SEM micrographs of fractured surfaces establish a synergetic effect of both ABS and TiO2 components in the epoxy matrix. The phenomenon such us cavitation, crack path deflection, crack pinning, ductile tearing of the thermoplastic, and local plastic deformation of the matrix with some minor agglomerates of TiO2 are observed. However, between these agglomerates, the particles are separated well and are distributed homogeneously within the polymer matrix. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

5.
《Ceramics International》2023,49(13):21667-21677
In recent years, researchers have been interested in incorporating inorganic nanoparticles into thermosetting epoxy composites to improve their mechanical properties. This research explores the diffusion of ball milled zircon (ZrSiO4) and anatase TiO2 nanoparticles with glass fibre reinforced epoxy polymer (GFRP) composites at the same weight percentages (0:0, 2.5:2.5, 5:5, and 7.5:7.5) to improve mechanical properties. The ZrSiO4 and TiO2 nanoparticles were prepared by an ultrasonic liquid processor, and composites were fabricated using the compression molding technique. The void percentage was calculated from the theoretical and measured densities of composites. Mechanical tests were conducted in accordance with ASTM standards. The particle sizes of zircon and titanium dioxide were calculated as 70.5 nm and 64.5 nm, respectively, using field emission scanning electron microscopy (FESEM), which reveals the fibre pullout, damaged interfaces, filler dispersion, and voids in specimens. The chemical composition, crystalline structure, and size were determined using X-ray diffraction (XRD). It was found that the GFRP composite with Zircon and TiO2 incorporated at a concentration of 5:5 wt% has a greater tensile strength of 74.34%, a tensile modulus of 18.14%, a flexural strength of 33.55%, a flexural modulus of 33.61%, a shore "D" hardness of 4.66%, and a capacity to absorb energy of 61.14% in notched specimens with neat GFRP. With filler addition, the percentage of elongation at failure in the 5:5 wt percent for the tensile test is 44.36%, and the flexural test is 24.38% higher than the neat sample. Hence, this work improves the GFRP composites' mechanical and structural properties.  相似文献   

6.
Hybrid coatings (inorganic‐organic) were prepared using a blown and epoxidized soybean oil as the organic matrix. Both TiO2 particles and titanium sol‐gel precursors (Titanium tetra‐i‐propoxide, TIP; titanium (di‐i‐propoxide) bis(acetylactonate), TIA) were incorporated into the coating. Three sizes of TiO2 particles ranging from 32 nm to 500 nm were used for comparison with the metal‐oxo‐clusters. General mechanical coating properties, tensile properties, and viscoelastic properties of the sol‐gel (ceramer) system were evaluated for the coatings, and the sol‐gel derived metal‐oxo‐clusters were found to have higher tensile modulus, storage modulus (E ′), and Tg compared with the TiO2 particles.  相似文献   

7.
Nylon 1010 composites filled with two types of surface‐modified SiO2 nanoparticles (RNS and DNS) were prepared by melt blending. The mechanical properties of the composites were evaluated. The influences of the surface‐modified nano‐SiO2 on the thermal stability, crystallization behavior, and microstructure of nylon 1010 were investigated by thermogravimetric analysis, differential scanning calorimetry (DSC), X‐ray diffraction, and transmission electron microscopy. And the interfacial interactions between the fillers and polymer matrix were examined using a Fourier transformation infrared spectrometer. It was found that the addition of the surface‐modified nano‐SiO2 had distinct influences on the thermal stability, mechanical properties, and crystallization behavior of nylon 1010. RNS and DNS as the fillers had different effects on the mechanical properties of nylon 1010. The composites filled with RNS at a mass fraction of 1–5% showed increased break elongation, Young's modulus, and impact strength but almost unchanged or even slightly lowered tensile strength than the unfilled matrix. The DNS‐filled nylon 1010 composites had obviously decreased tensile strength, whereas the incorporation of DNS also contributed to the increase in the Young's modulus of nylon 1010, but less effective than RNS. Moreover, the nylon 1010 composites had better thermal stability than the neat polymer matrix, and the composites filled with RNS were more thermally stable than those filled with DNS. The difference in the crystallinity of neat nylon 1010 and its composites filled with RNS and DNS was subtle, although the surface‐modified nano‐SiO2 could induce or/and stabilize the γ‐crystalline formation of nylon 1010. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

8.
Microstructural characterization of nylon 6/short glass fiber (SGF) and nylon 6/polyacrolonitrile based carbon fibers (PAN‐CFs) of 10 to 40 wt% has been performed by positron lifetime technique (PLT). The positron lifetime parameters viz., o‐Ps lifetime (τ3), o‐Ps intensity (I3), and fractional free volume (Fv) of nylon 6/SGF and nylon 6/PAN‐CF composites are correlated with the mechanical properties viz., tensile strength and Young's modulus. The Fv shows negative deviation with the reinforcement of 10 to 40 wt% of PAN‐CF and show positive deviation in nylon 6/SGF from the linear additivity relation. The negative deviation in nylon 6/PAN‐CF composite suggests the induced molecular packing due to the chemical interaction between the polymeric chains of nylon 6 and PAN‐CF. The positive deviation in nylon 6/SGF composite indicates the formation of interface between the polymeric chains of nylon 6 and SGF. The increased crystallinity of nylon 6/SGF and nylon 6/PAN‐CF composites shows the improved mechanical properties of the composites. The hydrodynamic interaction parameter (h), which shows more negative values in nylon 6/SGF than nylon 6/PAN‐CF composites. However, the extent of chemical interaction in nylon 6/SGF is less compare to nylon 6/PAN‐CF composites. This is evident from Fourier transform infrared spectrometry studies. POLYM. ENG. SCI., 58:1428–1437, 2018. © 2017 Society of Plastics Engineers  相似文献   

9.
The mechanical and thermophysical properties of TiO2‐filled chlorobutyl rubber composites were investigated. These materials exhibited enhanced mechanical properties such as increased modulus, tensile strength, and hardness. The morphology of filler dispersion in the matrix was analyzed by scanning electron microscopy and atomic force microscopy. Moreover, the effect of TiO2 content on the molecular transport of solvents was examined by means of degree of swelling, volume fraction of rubber, penetration rate of solvent, mean diffusion coefficient, etc. A periodic method was used to estimate the thermophysical behavior of samples. It was shown that the thermal conductivity and diffusivity of composites increase with increasing of TiO2 filler content. Finally, the utilization of the material as effective chemical protective clothing against volatile organic chemicals was analyzed. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers  相似文献   

10.
TiO2 nanofillers (5 nm, 0–15% weight) have been introduced in the PMMA matrix using a twin screw extruder to increase the performance of PMMA. The twin screw extrusion process is optimized to disperse the particles into PMMA. Nanofiller infusion improves the thermal, mechanical, and UV absorption properties of PMMA. TiO2‐PMMA nanocomposites exhibit the increase in tensile modulus (?90%), decomposition temperature (?31%), dimension stability (~ 60%) and UV absorption (~ 410%). Properties of the nanoTiO2‐PMMA composites are depending on the dispersion of TiO2 in the PMMA matrix. It is interrelated with loading. Formation and disappearance of the peaks in FTIR confirm the chemical interaction of PMMA with TiO2. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

11.
Micrometer and nanometer TiO2 particle‐filled poly(phthalazine ether sulfone ketone) (PPESK) composites with various filler volume fractions from 0.5 to 7.5 vol % were prepared by heating compression molding. The friction and wear behaviors of the PPESK composites were evaluated using the block‐on‐ring test rig by sliding PPESK‐based composite blocks against a mild carbon steel ring under dry friction conditions. The wear debris and the worn surfaces of the PPESK composites filled with micrometer and nanometer TiO2 particles were investigated by using a scanning electron microscope (SEM), while the structures of PPESK composites and wear debris were analyzed with IR spectra. Experimental results show that antiwear properties of the PPESK composites can be improved greatly by filling nanometer TiO2 particles, and the friction coefficient decreases when the filler volume fraction is below 2.5%, but when the filler volume fraction is above 2.5% the friction coefficient increases gradually with increasing filler volume fraction. In the case of micrometer TiO2 filler, wear rates increase with increasing filler volume fractions under identical test conditions, and the friction coefficients are less sensitive to the filler volume fraction. It was also found that the wear mechanism of micrometer TiO2 particle‐filled PPESK is mainly severe adhesion and abrasive wear, while that of nanometer TiO2 particle‐filled PPESK is mainly slight abrasive wear. In the former case, there are no transfer film formed on the surface of the counterpart steel, and wear debris are in the form of long and large ribbon. While in the latter case, the wear debris was granule and their size was about 10 μm. In case of 1 vol % nanometer TiO2 particle‐filled PPESK composites, the transfer film was fairly thinner and smoother, and the transfer film provided better coverage on the surface of steel ring, while that of 7.5 vol % was thicker and discrete. These account for the different friction and wear behavior of micrometer and nanometer TiO2 particle‐filled PPESK composite. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 906–914, 2004  相似文献   

12.
An anisotropic structure arranged by fillers is an effective method to make composites possess special properties, but the conventional particle-reinforced polyurethane (PU) composites usually have an isotropic 0-3 structure. In this study, a precipitation method was used to synthesize TiO2 particles. The particles were dispersed in a PU matrix, and the structures were observed by scanning electron microscopy. The results indicate that in the presence of an applied electric field, 1-3-like composites with TiO2 particles in an oriented arrangement were prepared, while 0-3 PU composites were prepared without an electric field. Dynamic viscoelasticity test results show that the PU-TiO2 composites with a 1-3-like structure have a higher storage and loss modulus. The creep properties of these two kinds of PU composites were measured and further fitted with a Findley power law and Weibull model. It was found that the creep resistance and recovery properties of the PU composites were enhanced by the anisotropic structures of the filler particles in the matrix. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47450.  相似文献   

13.
Three different UV stabilizers, 2‐(2H‐benzotriazol‐2‐yl)‐4,6‐ditertpentylphenol (Tinuvin XT833), 2‐(2H‐benzotriazol‐2‐yl)‐p‐cresol (Tinuvin P), or rutile–titanium dioxide (TiO2) were incorporated into poly(vinyl chloride) (PVC) and wood/PVC (WPVC) composite, and mechanical and physical properties and photostabilities were monitored. The polyene and carbonyl sequences of PVC increased with UV weathering time and with presence of wood flour. The yellowness index increased because of polyene and carbonyl productions, whereas the brightness increased because of the photobleaching of lignin in wood. The photostabilities of PVC and WPVC could be improved through the use of UV stabilizers. Tinuvin P was recommended in this work as the most effective stabilizer for PVC and WPVC composites. The stabilization effect was interfered by presence of wood particles. The mechanical property changes corresponded well to the structural changes under UV for neat PVC. For WPVC composites, the presence of wood particles played more significant effect on the mechanical properties during UV aging than the UV stabilizer. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers  相似文献   

14.
《Polymer Composites》2017,38(8):1689-1697
The effects of hybrid filler of zinc oxide and chitosan (chitosan–ZnO) on thermal, flexural, antimicrobial, chemical resistance, and hardness properties of ultrahigh‐molecular‐weight polyethylene (UHMWPE) composites with varying concentration of zinc oxide (ZnO) and further hybridized by chitosan (CS) were successfully studied. The composites were prepared using mechanical ball milling and followed by hot compression molding. The addition of ZnO to the UHMWPE matrix had lowered the melting temperature (T m) of the composite but delayed its degradation temperature. Further investigation of dual filler incorporation was done by the addition of chitosan to the UHMWPE/ZnO composite and resulted in the reduction of UHMWPE crystallization. The flexural strength and modulus had a notably high improvement through ZnO addition up to 25 wt% as compared to neat UHMWPE. However, the addition of chitosan had resulted in lower flexural strength than that of 12 wt% ZnO UHMWPE composite but still higher than that of neat UHMWPE. It was experimentally proven that the incorporation of ZnO and chitosan particles within UHMWPE matrix had further enhanced the antimicrobial properties of neat UHMWPE. Chemical resistance was improved with higher ZnO content with a slight reduction of mass change after the incorporation of chitosan. The hardness value increased with ZnO addition but higher incorporation of chitosan had lowered the hardness value. These findings have significant implications for the commercial application of UHMWPE based products. It appears that these hybrid fillers (chitosan–ZnO)‐reinforced UHMWPE composites exhibit superior overall properties than that of conventional neat UHMWPE. POLYM. COMPOS., 38:1689–1697, 2017. © 2015 Society of Plastics Engineers  相似文献   

15.
A systematic research has been conducted to investigate the matrix properties by introducing nanosize TiO2 (5 nm, 2.0–30% by weight) filler into a poly (methyl methacrylate) (PMMA) resin. A twin screw extraction process was developed to disperse the particles into the PMMA. The thermal, mechanical, and viscoelastic properties of the virgin PMMA and nanoTiO2‐PMMA composite were measured. The nanofiller infusion improves the thermal, mechanical and viscoelastic properties of the PMMA. Nanocomposite shows increase in storage modulus (~ 60%), rubbery modulus (~ 210%), glass transition temperature (~ 27%), crosslink density (~ 213%), initial decomposition temperature (~ 83% at 1% wt. loss), and activation energy (~ 141%). Mechanical performance and thermal stability of the nanoTiO2‐PMMA composites are depending on the dispersion state of the TiO2 in the PMMA matrix. Scanning electron microscopic study shows that the particles are well dispersed in the PMMA matrix. They are correlated with loading. Kinetics for thermal degradation analysis was studies. The integral procedural decomposition temperature (IPDT) is enhanced (~ 117%). The nanocomposites of high activation energy possess high thermal stability. Interrelation of Tg, crosslink density, IPDT, storage modulus, activation energy, and TiO2 weight percent are established. Various reasons for these effects in terms of reinforcing mechanisms have been discussed. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

16.
Nylon‐6 and nanoclay/nylon‐6 composite nanofibers were prepared by electrospinning technique, in which formic acid was used as a solvent for good solubility of nylon‐6. The diameter of nylon‐6 and nanoclay/nylon‐6 nanofibers was below 350 nm and had smooth surfaces. The DSC heating curves of nylon‐6 and composites nanofibers show two endotherm behaviors, Tm1 (about 214°C) and Tm2 (about 220°C), corresponding to the melting events of γ‐form and α‐form crystals, respectively. The WAXs study showed that the γ‐crystalline phase predominantly present in both nylon‐6 and nanoclay/nylon‐6 nanofibers. The mechanical properties of the nanoclay/nylon‐6 composite nanofibers were higher than neat nylon‐6 electrospun nanofibers, which was decreased as the quantity of the clay increased. It might be due to the aggregation of nanoclay at high concentration. The thermal properties of the composite nanofibers were higher than neat nylon‐6 nanofibers. POLYM. COMPOS., 2012. © 2011 Society of Plastics Engineers  相似文献   

17.
Unidirectional glass fiber reinforced furfuryl alcohol (FA) composites have been prepared by the pultrusion processes. The optimum processing parameters of the glass fiber reinforced FA composites by pultrusion has been studied. The effects of the optimum processing parameters on the properties (flexural strength, flexural modulus, notched Izod impact strength, glass transition temperature (Tg), dynamic shear storage modulus (E'), shrinkage ratio, and roughness) investigated including die temperature, pulling rate, postcure temperature and time, and filler type and content. Results show that the pultruded composites possessed various optimum pulling rates at different die temperatures. On the basis of the DSC diagram, the swelling ratio and the mechanical properties of pultruded composites, the optimum die temperature can be determined. The mechanical properties and Tg increase at a suitable postcure temperature and time. Furthermore, the properties which decrease due to the degradation of pultruded composites for a long postcure time will be discussed. The mechanical properties of pultruded composites reach a maximum value at various filler content corresponding to the talc and calcium carbonate, respectively, and then decreased. When the fillers are added to the pultruded glass fiber reinforced FA composites, the shrinkage ratio of composites become smaller, and the surface of composites became smooth. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

18.
In situ polymerization method was used to prepare TiO2/polylactide (PLA) nanocomposites with different contents of TiO2 in this work. The size of the organically modified TiO2 particles was investigated by X‐ray diffraction (XRD) analysis. Scanning electron microscope (SEM) shows that nano‐TiO2 particles disperse in the PLA evenly when the content of TiO2 is low (less than 3 wt%). The differential scanning calorimeter (DSC), thermogravimetry analysis (TGA), and tensile test were used to study the thermal and mechanical properties of the composites. Results show that both the thermal and mechanical properties are markedly improved when the content of TiO2 is 3 wt%. UV light irradiation and solution degradation experiment show that degradation of the composites is higher when the content of TiO2 increases and due to the introduction of TiO2 particles in the nanocomposites, the TiO2/PLA nanocomposites exhibit remarkable bacteriostasic activity. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers  相似文献   

19.
Poly(L ‐lactic acid)‐titanium dioxide nanocomposites (with various loadings of TiO2: 0.5, 1, 2, 5, and 10 wt %) were produced by solution casting method. The influence of TiO2 on thermal properties and crystallinity of PLA was investigated by DSC and FTIR spectroscopy. The TiO2 nano filler has no significant influence on the characteristic temperatures (Tg, Tc, and Tm), but has high impact on the crystallinity of these systems. The degree of crystallinity Xc significantly increases for PLA nanocomposites loaded with up to 5 wt % of TiO2, while for 10 wt % load of TiO2 it drops below Xc of the pure resin. The degradation of the prepared composites was evaluated hydrolytically in 1N NaOH, enzymatically in α‐amylase solutions, and under UV irradiation. The catalytic effect of TiO2 nano particles on the degradation processes under UV light exposure (λ = 365 nm) and hydrolytic degradation was confirmed with the increase of the filler content. The opposite effect was identified in enzymatic degradation experiments. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

20.
ABSTRACT: Toluene-2,4-diisocyanate and dodecanol were used to chemically functionalize nanosilica (TDID-SiO2). Composites of TDID-SiO2 and oil-impregnated monomer casting nylon (OMC nylon) were prepared by an in situ anionic ring-opening polymerization. The dispersion of the TDID-SiO2 in oil was studied along with the mechanical and friction properties of the composites. The results show that the dispersion of the TDID-SiO2 in oil was significantly enhanced. Specifically, some TDID-SiO2 was wrapped in oil droplets, and the size of the oil droplets increased from 2.3 to 3.3 μm for 0–0.125 wt % of the TDID-SiO2 nanoparticles, which was confirmed by scanning electron microscopy. The composites exhibited excellent mechanical properties when 0.10 wt % TDID-SiO2 was integrated into OMC nylon. The tensile strength, elastic modulus, notched impact strength, flexural strength, and flexural modulus increased by 6.9%, 7.1%, 33.2%, 15%, and 77.5%, respectively, compared to OMC nylon without TDID-SiO2 nanoparticles. The friction coefficient was effectively controlled and the abrasion quantity was reduced. Thermogravimetric analysis showed that the thermal decomposition temperature was also improved. The improved mechanical and frictional properties of TDID-SiO2/OMC nylon composite will enhance its application in wear-resistant products in heavy industry. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 46994.  相似文献   

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