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1.
The novel surface‐modified sepiolite/unsaturated polyester (sepiolite/UP) nanocomposites were prepared by in situ polymerization. Sepiolite fibers were first organo‐modified by grafting of vinyltriethoxysilane (VTS) containing a double bond onto the surfaces and used as nanofillers. The morphology of sepiolites and nanocomposites were characterized by X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), and transmission electron microscope (TEM). Moreover, the thermal properties were determined by thermogravimetric analysis (TGA) and the thermal degradation mechanism was discussed. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
2.
Chinnakkannu Karikal Chozhan Muthukaruppan Alagar Rajkumar Josephine Sharmila Periyannan Gnanasundaram 《Journal of Polymer Research》2007,14(4):319-328
The intercrosslinked networks of unsaturated polyester (UP) toughened epoxy–clay hybrid nanocomposites have been developed.
Epoxy resin (DGEBA) was toughened with 5, 10 and 15% (by wt) of unsaturated polyester using benzoyl peroxide as radical initiator
and 4,4′-diaminodiphenylmethane as a curing agent at appropriate conditions. The chemical reaction of unsaturated polyester
with the epoxy resin was carried out thermally in presence of benzoyl peroxide-radical initiator and the resulting product
was analyzed by FT-IR spectra. Epoxy and unsaturated polyester toughened epoxy systems were further modified with 1, 3 and
5% (by wt) of organophilic montmorillonite (MMT) clay. Clay filled hybrid UP-epoxy matrices, developed in the form of castings
were characterized for their thermal and mechanical properties. Thermal behaviour of the matrices was characterized by differential
scanning calorimetry (DSC), thermo gravimetric analysis (TGA) and dynamic mechanical analysis (DMA). Mechanical properties
were studied as per ASTM standards. Data resulted from mechanical and thermal studies indicated that the introduction of unsaturated
polyester into epoxy resin improved the thermal stability and impact strength to an appreciable extent. The impact strength
of 3% clay filled epoxy system was increased by 19.2% compared to that of unmodified epoxy resin system. However, the introduction
of both UP and organophilic MMT clay into epoxy resin enhanced the values of mechanical properties and thermal stability according
to their percentage content. The impact strength of 3% clay filled 10% UP toughened epoxy system was increased by 26.3% compared
to that of unmodified epoxy system. The intercalated nanocomposites exhibited higher dynamic modulus (from 3,072 to 3,820 MPa)
than unmodified epoxy resin. From the X-ray diffraction (XRD) analysis, it was observed that the presence of d
001 reflections of the organophilic MMT clay in the cured product indicated the development of intercalated clay structure which
in turn confirmed the formation of intercalated nanocomposites. The homogeneous morphologies of the UP toughened epoxy and
UP toughened epoxy–clay hybrid systems were ascertained from scanning electron microscope (SEM). 相似文献
3.
Mechanical and thermal properties of modified kaolin clay/unsaturated polyester nanocomposites
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The improvement in thermal and mechanical properties of Nanocomposites prepared with unsaturated polyester (UP) as polymer matrix and various loadings of amino‐modified nano kaolinite clay as filler has been studied. Mechanical stirring and ultrasonication resulted in better dispersion of the clay. For curing polyester resin, cobalt naphthenate was used as accelerator and MEKP as initiator. Dynamic Mechanical Analysis (DMA) was carried out to find storage and loss modulus. Thermal stability was found through thermogravimetric analysis and the evaluation of structure and morphology of the nanocomposites were done through XRD, SEM, and TEM. Nanocomposite with 3 phr of amino modified clay has shown higher storage modulus and an improved thermal stability of UP/clay nanocomposites has been established. Tensile strength and toughness of the composite have been found to achieve maximum values at 1 phr of clay and the storage modulus has had an improvement of 38% compared to neat UPR. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43245. 相似文献
4.
Unsaturated polyester (UP)/montmorillonite (MMT) nanocomposite was prepared by using hydroxypropylacrylate (HPA) as a reactive diluent instead of conventional styrene monomer and the effect of polarity of reactive diluent on properties of nanocomposite was investigated. X‐ray and mechanical test data indicated that mixing for an extended period of time is essential to enhance the physical properties of nanocomposites in the UP/Cloisite 6A system. This was attributed to the high polarity of HPA that may disturb the preintercalation of UP resin into the galleries of MMT. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 238–242, 2004 相似文献
5.
Unsaturated polyester/styrene (UP ) resin was filled with nanodiamonds (NDs ) containing carboxyl and methacrylate functionalities using mechanical mixing. Field emission SEM exhibited a uniform dispersion of tightly bound aggregates of nanosized spherical NDs with good interfacial interaction. Rheological measurements exhibited a step increment in the shear viscosity of a UP /ND suspension at 0.6 wt% ND resembling a percolation state at this loading. Shear viscosity data supported by dynamic mechanical analysis results suggested the development of effective ND particles in which ND aggregates were covered by only polyester macromolecules. Accordingly, the morphology of UP /ND composites approached a quasi‐percolation state at 0.6 wt% in which effective ND particles were connected thoroughly, instead of direct ND ?ND contact, forming a co‐continuous polyester phase covering the ND particles. Based on such morphology, DSC and Fourier transform infrared analysis suggested the development of heterogeneous microgels in cured UP resin containing NDs which in turn governed the overall mechanical properties of the composites. © 2017 Society of Chemical Industry 相似文献
6.
This work studies the development of varying weight percentages (0.5, 1.0, and 1.5 wt%) of surface functionalized mullite reinforced unsaturated polyester (UP) composites and their thermal, dielectric, water absorption, and mechanical properties. The synthesized mullite was functionalized with vinyltriethoxysilane (VTES). The introduction of vinyl groups on the surface of mullite was confirmed by FT‐IR, TGA, and X‐ray diffraction (XRD) analyses. Varying weight percentages (0.5, 1.0 and 1.5 wt%) of vinyl functionalized mullite (VFM) were incorporated into UP resin with a benzoyl peroxide initiator to obtain composites. The resultant data obtained from thermal, mechanical, dielectric, and water absorption studies, indicate that incorporation of VFM, leads to a significant improvement in the thermo mechanical, dielectric, and moisture resistant properties of the UP composites, compared with those of neat UP matrices. The molecular dispersion of VFM fiber in reinforced UP matrix composites was confirmed by SEM analysis. POLYM. COMPOS., 35:1663–1670, 2014. © 2013 Society of Plastics Engineers 相似文献
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8.
Bio‐based calcium carbonate nanoparticles (CaCO3) were synthesized via size reduction of eggshell powder using mechanical attrition followed by high intensity ultrasonic irradiation. The transmission electron microscopic (TEM) and BET surface area measurements show that these particles are less than 10 nm in size and a surface area of ~44 m2/g. Bio‐based nanocomposites were fabricated by infusion of different weight fractions of as‐prepared CaCO3 nanoparticles into Polylite® 31325‐00 resin system using a non‐contact Thinky® mixing method. As‐prepared bio‐nanocomposites were characterized for their thermal and mechanical properties. TEM studies showed that the particles were well dispersed over the entire volume of the matrix. Thermal analyses indicated that the bio‐nanocomposites are thermally more stable than the corresponding neat systems. Nanocomposite with 2% by weight loading of bio‐CaCO3 nanoparticles exhibited an 18°C increase in the glass transition temperature over the neat Polylite 31325 system. Mechanical tests have been carried out for both bio‐nanocomposites and neat resin systems. The compression test results of the 2% Bio‐CaCO3/Polylite 31325 nanocomposite showed an improvement of 14% and 27% in compressive strength and modulus respectively compared with the neat system. Details of the fabrication procedure and thermal and mechanical characterizations are presented in this article. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1442–1452, 2013 相似文献
9.
10.
UV-curable waterborne unsaturated polyesters for wood coatings were prepared. The effects of different polyols and acids on the properties of the UV-curable waterborne unsaturated polyesters were investigated. Several different unsaturated polyester prepolymers were prepared from three different polyols [ethylene glycol (EG), diethylene glycol (DEG), and propylene glycol (PG)] and three different acids [tetrahydrophthalic anhydride (THPAn), terephthalic acid (TPA), and trimellic anhydride (TMAn)]. UV-curable coating materials were formulated from the prepolymers and 2-hydroxy-2-methylphenyolpropane-1-one as a photoinitiator with distilled water as a diluent. Trimethylolpropane diallyl ether was used as an air inhibitor of cure. The dynamic mechanical studies showed the properties of those unsaturated polyesters were well correlated with their glass transition temperature behaviors. It was found that the unsaturated polyester prepared with 60/40 (mol %) TMAn/THPAn and the equimolar mixture of EG, DEG, and PG showed balanced coating properties such as good tensile properties and weatherability, as well as proper viscosity (ca. 2500 cps) when using distilled water as a diluent. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 695–708, 1998 相似文献
11.
Dynamic rheology, differential scanning calorimetry and in situ Fourier transform infrared spectroscopy were used to study the cure behavior of unsaturated polyester/modified montmorillonite nanocomposites. The results showed that their gel times increased markedly at the same cure temperature, and that the activation energy of the nanocomposites was higher than that of the pure unsaturated polyester. Their peak temperatures of enthalpy increased as well. The total exotherm of the cure reaction declined and the cure rate decreased. In the curing process of pure unsaturated polyesters, the conversion of styrene was higher than that of the double bonds on unsaturated polyester macromolecular chains. The cure mechanism of the unsaturated polyester/modified montmorillonite changed because of the presence of double bonds in the layers of modified montmorillonite. However, the conversion of styrene in the nanocomposites was lower than that of double bonds on unsaturated polyester chains during cure at room temperature, and the conversion of styrene was increased after post‐curing and was higher than that of the double bonds on unsaturated polyester chains at the end of the cure reaction. Moreover, the degree of reaction of double bonds on unsaturated polyester chains of the nanocomposites was higher than that of unsaturated polyesters. Copyright © 2006 Society of Chemical Industry 相似文献
12.
Jinkyung Kim Dookyo Jeong Changho Son Younghee Lee Eunyong Kim Il Moon 《Korean Journal of Chemical Engineering》2007,24(6):1076-1083
Three types of unsaturated polyester resins were synthesized from the glycolysis of polyethylene terephthalate (PET) plastic
waste, considering environment, cost and properties for their applications. These synthesized unsaturated polyester resins
could be used for various construction processes and materials such as no dig pipelining (NDR-1), pultrusion (PLR-1) and polymer
concrete (PCR-1). PET was taken from common soft-drink bottles, and ethylene glycol (EG), diethylene glycol (DEG) and MPdiol
glycol mixtures were used for the depolymerization at molar ratios. The glycolyzed PET 1
st
products (oligomers) were reacted with maleic anhydride, phthalic anhydride and dicyclopentadiene (DCPD) (especially for
polymer concrete) to form unsaturated polyester resins with mixed styrene. The lab scale (1–5 kg) and pilot plant scale-up
tests (200 kg) were experimented to evaluate the processing characteristics, viscosity, acid number and curing behaviors.
The main properties such as hardness, flexural strength, tensile strength, heat distortion temperature, elongation, and chemical
resistance were determined based on the various uses of the three resins. Furthermore, the applicability and the properties
of these developed resins were verified through many real application tests. 相似文献
13.
不饱和聚酯型人造大理石的力学性能 总被引:3,自引:2,他引:1
简述了不饱和聚酯(UPR)型人造大理石的制备工艺。研究了质量比为4∶1的Al(OH)3/Ca(OH)2复合填料用量对不饱和聚酯型人造大理石力学性能的影响,对制得的人造大理石的耐腐蚀性进行了测试,采用光学显微镜观察了试样腐蚀前后的表面形貌。结果表明,在复合填料与UPR质量比为1.86∶1时,弯曲强度、压缩强度达到最大,分别为55.88 MPa和96.04 MPa。甲苯对人造石的腐蚀作用最大,氢氧化钠次之,硫酸腐蚀作用较小,腐蚀介质主要对不饱和树脂聚合物产生腐蚀,从而导致人造石力学性能降低。 相似文献
14.
SiC颗粒增强不饱和聚酯树脂复合材料的力学性能 总被引:1,自引:0,他引:1
采用万能试验机和硬度计测试研究了SiC颗粒含量和粒径对不饱和聚酯树脂基复合材料力学性能的影响,通过扫描电子显微镜观察了拉伸试样的端口形貌。结果表明,填充的SiC质量分数为10%时,其不饱和聚酯树脂复合材料拉伸强度达到最大,8000目、1000目SiC填充体系拉伸强度分别为53.2MPa,44.8MPa,较纯树脂体系提高68.1%,41.5%。当SiC质量分数为30%时,SiC填充体系的弹性模量较纯树脂体系提高25.8%以上,硬度提高2.3%以上,SiC颗粒尺寸对复合材料的弹性模量和硬度影响不大。SiC/不饱和聚酯树脂复合材料的断裂属脆性断裂。 相似文献
15.
M. Monti A. Terenzi M. Natali I. Gaztelumendi N. Markaide J. M. Kenny L. Torre 《应用聚合物科学杂志》2010,117(3):1658-1666
In this work, the dispersion of carbon nanofibers (CNFs) in an unsaturated polyester (UP) resin was performed by mean of the calendering process. The calendering process allows to obtain good dispersion of the nanoparticles, and, with respect to the other techniques, is also possible to scale it up at the industrial level. Optimization of the calendering conditions for the processing was carried out as a first step of this study. Optimization, in this case, means to reach the best dispersion level, as rapidly as possible and with the lowest amount of styrene evaporation. The dispersion level reached was investigated by the technique of scanning electron microscopy. The investigation on electric conductivity of the nanocomposites at different CNF concentrations has revealed that the electrical percolation threshold exists at around 0.3 wt %, where electrical conductivity switches from 10?13 to 10?7 S/cm. The rheological characterization has been performed to verify if the improved electrical properties are obtained at the expense of loss of workability, that is a significant increase of viscosity. Eventually, a mechanical characterization was carried out. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
16.
M. Aminzare A. Eskandari M.H. Baroonian A. Berenov Z. Razavi Hesabi M. Taheri S.K. Sadrnezhaad 《Ceramics International》2013
Two different hydroxyapatite based composites reinforced by oxide ceramic (20 wt%) nano crystals were synthesized by high-energy ball milling and sintered by pressure less technique. Alumina and titania nanoparticles as secondary phases improved densification and mechanical behavior of apatite and postponed its decomposition to the tricalcium phosphate (TCP) phases at elevated temperatures. Increasing the relative density of apatite using nano reinforcements leads to enhance the bending strength by more than 40% and 27% (as compared to the pure HA) and increase the hardness from 2.52 to 5.12 (Al2O3 composite) and 4.21 (TiO2 addition) GPa, respectively. Transmission electron microscopy (TEM), scanning electron microscopy (SEM) and X-ray diffraction spectroscopy were employed to study morphologies, fracture surfaces and phase compositions, respectively. The morphological study and micro structural analysis confirm the X-ray diffraction and relative density diagrams. 相似文献
17.
18.
This article deals with the synthesis and properties of poly[(propylene glycol maleate)-co-(propylene glycol phthalate)] diol (PGMPD)/polyester–urethane or polyether–urethane hybrid polymer networks (HPNs). The polyurethane type and the molar ratio of NCO/OH have an effect on their properties. The structure–property relationship is discussed as well. © 1994 John Wiley & Sons, Inc. 相似文献
19.
A novel modified-unsaturated polyester resin (M-UPR) with phosphorus-containing pendant groups was successfully prepared by employing a bifunctional acid, 2-[10-(9,10-dihydro-9-oxa-10-phosphaphenantrene-10-oxide-10-yl)]-maleic acid (DOPO-MA) as monomer. Characterization of DOPO-MA and M-UPR was performed using element analysis, 1H-NMR, or FT-IR. The curing of M-UPR was measured by differential scanning calorimetry, and the optimal cure temperature was calculated with DSC curves at different heating rates. The thermal stability was investigated with thermogravimetric analysis and comparative FT-IR analysis for char residue before and after heating. The flame-retardant property was determined by limiting oxygen index measurements and UL94 flammability meter. The viscoelastic property was measured with dynamic mechanical analysis. Owing to the incorporation of the rigid structure of pendant phosphorus groups, both thermal stability and flame retardancy of the resultant M-UPR have been improved. 相似文献
20.
Ahmad Mousa Michaela Gedan-Smolka Udo Wagenknecht Sami Massadeh 《Journal of Adhesion Science and Technology》2020,34(15):1609-1627
AbstractTo determine the potential of a sustainable by-product from iron-making industry ‘Slag’ as reinforcing agent for thermoset polymer composite, particularly unsaturated polyester (UPE). The slag has been coated by reactive and nonreactive silanes. In the first stage, the slag was comminuted and sifted prior to silane coating. The silane-coating agent adsorbed on the surface of the slag was followed by thermogravimetric analysis (TGA) and attenuated total reflectance infrared spectroscopy (ATR-IR). The fabricated composites with various silane-coated slag were inspected with respect to tensile and flexural properties as a function of the coating agent. Scanning electron microscope was carried out on the composite with uncoated and silane-coated samples. The obtained findings indicated that the slag coated with amino and octyltrioxy-based silanes showed a positive impact on the mechanical performance. The improvement was related to the structure of coupling agent used. 相似文献