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1.
Rubber seed oil (RSO) and its derivatives, heated rubber seed oil (HRSO) and alkyd resins were evaluated as binders in air drying solvent and waterborne coatings. HRSO was obtained by heating RSO at 300±5°C until the desired viscosity. Acid value of RSO (53) is somewhat high. The major saturated fatty acids are palmitic (10.2%) and stearic (8.7%) while the main unsaturated fatty acids are oleic (24.6%), linoleic (39.6%) and linolenic (16.3%). Naturally, RSO is semi-drying and heating enhances its drying ability. GPC analysis reveals that RSO consists of a rather high molecular weight fraction that is rarely found in commonly known vegetable oils. The average molecular weight of RSO is higher than that of HRSO with the latter narrower in molecular weight distribution. Low molecular weight species constitute greater proportion of the alkyds and their number average molecular weights range between 1379 and 3304 which are comparable to those of commercial alkyds. The narrower the size distribution the better the quality of these alkyds as binders. Physico-chemical properties of solvent-borne alkyds vary with oil length (OL) and they are optimum at 50% OL. Water-borne alkyds investigated show that the sample with lower oil content contains lower volatile organic content. All the alkyd samples and HRSO are fairly resistant to water and alkali while they are virtually unaffected by acid and salt solutions. However, samples IV and V (water-borne alkyds) are more resistant than their solvent-borne counterparts (samples I–III) but exhibited lower scratch/gouge pencil hardness.  相似文献   

2.
This work deals with the preparation of alkyd resins from neem oil and their utilization in preparation of polyurethane coatings. Alkyd resins were synthesized by reaction of neem oil monoglycerides with four different divalent acids like phthalic anhydride, maleic anhydride, itaconic acid, and dimer fatty acid. The alkyds formation was studied by determining the acid number of the reaction mixture at regular intervals of time and the extents of the polyesterification reactions were calculated during the formation of alkyds. The structures of synthesized alkyds were confirmed by FT‐IR and 1H‐NMR spectroscopic analysis and also by end group analysis such as hydroxyl and acid values. The synthesized alkyds were reacted with TDI to prepare PU coatings and their performance was compared with PU coatings prepared from a commercial alkyd.  相似文献   

3.
Alkyd resins of 40% (I), 50% (II), and 60% (III) oil length (OL) were prepared with rubber seed oil (RSO), phthalic anhydride (PA), and glycerol (GLY), employing the two‐stage alcoholysis method. Changes in the physical characteristics of the reaction medium were monitored by determination of the acid value and the number‐average molecular weight, Mn , of in‐process samples withdrawn at different stages of the reaction. The mode of variation of these properties denotes that the preparation of RSO alkyds is complex. Molecular weight averages and the molecular weight distribution (MWD) of the finished alkyds were determined by GPC, cryoscopy, and end‐group analysis. Molecular weight averages and the MWD vary with differences in the formulation, with sample II exhibiting the narrowest size distribution. Values of Mn with the corresponding polydispersities in brackets are 3234 (1.91), 1379 (1.56), and 3304 (2.56) for samples I, II, and III respectively. Mn values obtained by cryoscopy are comparable to those obtained by gel permeation chromatography (GPC), while end‐group analysis seems to grossly overestimate their molecular weights. Correlation of Mn and the MWD with the quality of the finished alkyds shows that the narrower the size distribution the better the quality of the alkyd. Properties such as the rate of drying and resistance of the alkyds are optimum at 50% OL. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 79: 2431–2438, 2001  相似文献   

4.
Polypropylene (PP)/polyamide blends were compatibilized with PP modified with vinylsilane or maleic anhydride and ethylene–propylene random (EPR) copolymer modified with maleic anhydride. The thermal behavior, mechanical properties, and morphology of the blends were investigated. Thermal analysis showed that the polyamide crystallization temperatures shifted downward with all compatibilizers, whereas its melting behavior did not change. On the other hand, polypropylene crystallization temperatures shifted upward in all cases, except for blends containing EPR modified with maleic anhydride. Tensile strength and elongation at break increased for blends compatibilized with modified PP. Blends containing up to 7% of EPR modified with maleic anhydride did not show good yield stresses. The morphology of the blends showed a finer dispersion of the polyamide minor phase in the PP matrix. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2492–2498, 2003  相似文献   

5.
Polyesters were synthesized with monoglycerides prepared from rubber seed oil, a renewable resource. Monoglycerides were obtained by an alcoholysis method from the oil, which was neat or modified by treatments with different amounts of maleic anhydride at 230°C. The polyester resins were subsequently prepared by the condensation polymerization of the monoglycerides with phthalic anhydride. The monoglycerides and resins were characterized by spectroscopic analysis and measurements of the physicochemical properties. The chemical resistance of the polyesters was also studied. The results revealed that the polyesters prepared from the modified monoglycerides possessed better properties. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3748–3755, 2006  相似文献   

6.
Simple blends with different viscosity ratios of the components as well as compatibilized blends varying both in type and content of the compatibilizers were used to study the relation between the interfacial tension and the dispersed‐phase particle size for PP/PA6 (80/20 wt %) blends in this work. Four compatibilizing systems including poly(ethylene‐co‐methacrylic acid) ionomers, a maleic anhydride‐grafted propylene copolymer, maleic anhydride‐grafted polypropylene, and a maleic anhydride‐grafted styrene ethylene butylene copolymer were used. For blends prepared in an internal mixer, a power‐law relation was found between the capillary number and the torque ratio of the blends' components. This relation was used to estimate the interfacial tension for the compatibilized blends. The relation between the steady‐state torque of the blends as a measure of viscosity and the estimated values of interfacial tension were also investigated. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 54–63, 2003  相似文献   

7.
Acrylic-grafted-alkyd resins were prepared by free radical chemistry. Long, medium, and short oil alkyds were prepared using soybean oil, glycerol, phthalic anhydride (PA), and tetrahydrophthalic anhydride (THPA) and used as the alkyd phase. Acrylic co-monomer formulas containing methyl methacrylate (MMA), butyl acrylate (BA), methacrylic acid (MAA), and vinyl trimethoxysilane (VTMS) were polymerized in the presence of the different alkyds using 2,2′-azobisisobutyronitrile (AIBN) as the initiator to obtain the final grafted structures. Design of experiments was used to understand how different variables in the synthesis of the acrylated-alkyds affect the film performance. A Box–Behnkin design was used, varying the oil length of the alkyd phase, the degree of unsaturation in the polyester backbone, and acrylic to alkyd ratio. Acrylic–alkyd hybrid resins were reduced with an amine/water mixture. The hydrolytic stability of hybrid alkyd dispersed in water was evaluated. Cured films were prepared and basic coatings properties were also evaluated. It was found that the oil length of the alkyd is the most dominant factor for final coatings properties of the resins. The hydrolytic stability was dependent on the acrylic to alkyd ratio. The oil length of the alkyd backbone had a minimal effect on stability of the resin and film performance.  相似文献   

8.
Acrylic monomers were grafted onto alkyds via free radical chemistry. The alkyd was a medium oil soya-based alkyd with glycerol, phthalic anhydride, and tetrahydrophthalic anhydride (THPA) as the other components. To identify the specific graft locations, 1D and 2D NMR spectroscopy techniques were utilized. Gradient heteronuclear multiple quantum coherence (gHMQC) 2D NMR was required to assign the chemical shifts of the 1D carbon and proton NMR spectra. Three acrylic monomers, methyl methacrylate (MMA), butyl acrylate (BA), and methacrylic acid (MAA) were grafted to the alkyd, resulting in either MMA, BA, or MAA modified alkyds. Two-dimensional gHMQC spectra for each system confirm grafting at doubly allylic hydrogens located on the fatty acid chains and the polyol segment of the alkyd backbone. The gHMQC spectra show no evidence of grafting across double bonds on either pendant fatty acid groups or THPA unsaturation sites for any of the monomer choices.  相似文献   

9.
An unsaturated polyester resin was prepared that was based on the reaction of oligomers obtained from the depolymerization of poly(ethylene terephthalate) waste products, with both maleic anhydride and sebacic acid. The structure of the produced polyester was compared with that prepared from the reaction of dimethyl terephthalate with both maleic anhydride and sebacic acid with IR and NMR spectroscopy. Water‐extended polyester resins were prepared from these two polyesters through curing with styrene in the presence of various amounts of water with benzoyl peroxide as an initiator. The mechanical properties of the prepared water‐extended polyesters, as well as scanning electron microscopy, were investigated. The use of water‐extended polyesters based on recycled poly(ethylene terephthalate) waste for the preparation of decorative art objects and statues was investigated. Therefore, three pharaonic statues representing Tutankhamen, Nefertiti, and a black head of a cat were prepared. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3693–3699, 2003  相似文献   

10.
This work describes the synthesis and macromolecular reactions of maleic anhydride (MA)–acrylic acid (AA) binary reactive copolymers with γ‐aminopropyltriethoxysilane (APTS) as a polyfunctional crosslinker. Copolymers with a given composition of MA–AA (47.17–52.83 wt %) were synthesized by radical binary copolymerization with benzoyl peroxide as an initiator in p‐dioxane at 70°C in nitrogen atmosphere and initial monomer ratio of 1 : 1. It is shown that the network structure is formed in MA–AA/APTS in water by intermolecular reaction between the anhydride unit and the amine group, as well as between the etoxysilyl fragment and free carboxyl groups of the acrylic acid and maleic anhydride unit. Swelling parameters such as beginning time of hydrogel formation, initial rate of swelling, swelling rate constant, equilibrium swelling, and equilibrium water content were determined for copolymer/APTS/water systems with various copolymer/crosslinker ratios. Formation of a hyperbranched network structure through the fragmentation of side‐chain reactive groups in the studied systems was confirmed by FTIR, TGA, and DSC methods. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 4009–4015, 2003  相似文献   

11.
The effects of maleic anhydride modified ethylene–propylene–diene rubber (EPDMMA) and maleic anhydride modified ethylene–vinyl acetate (EVAMA) on the compatibilization of nitrile rubber (NBR)/ethylene–propylene–diene rubber (70:30 w/w) blends vulcanized with a sulfur system were investigated. The presence of EPDMMA and EVAMA resulted in improvements of the tensile properties, whereas no substantial change was detected in the degree of crosslinking. The blend systems were also analyzed with scanning electron microscopy and dynamic mechanical thermal analysis. The presence of EVAMA resulted in a blend with a more homogeneous morphology. The compatibilizing effect of this functional copolymer was also detected with dynamic mechanical analysis. A shift of the glass‐transition temperature of the NBR phase toward lower values was observed. The presence of EPDMMA and EVAMA also increased the thermal stability, as indicated by an improvement in the retention of the mechanical properties after aging in an air‐circulating oven. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2408–2414, 2003  相似文献   

12.
UV curable coating is a form of green technology that reduces or eliminates completely the emission of volatile organic compounds (VOC) and is in line with the current global call in preserving nature. The objective of this project is to produce UV curable resins from non-self drying palm stearin alkyds by the incorporation of maleic anhydride (MAH) which could introduce more unsaturation into the main chains of alkyds. Four alkyds with different level of unsaturation were prepared and the successful incorporation of MAH was confirmed by FTIR and 1H NMR analyses. Methyl methacrylate (MMA) was used as the reactive diluents, and benzophenone as the UV-photoinitiator. The UV-cured coatings were tested using standard methods adopted from ASTM, and results showed that coatings of maleated alkyds exhibited good film properties. This novel approach has succeeded in converting a non-self drying palm stearin alkyd into UV-curable resins.  相似文献   

13.
The application of rubber seed oil (RSO) and epoxidized RSO (ERSO) as a plasticizer in acrylonitrile butadiene rubber (NBR) was studied using RSO and ERSO with different levels of epoxidation. The results indicated that ERSO could be used as a less leachable and low volatility plasticizer for NBR. The use of ERSO in NBR gave better abrasion resistance whereas the tensile strength and tear strength were comparable to those vulcanizates that contained dioctyl phthalate as a plasticizer. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 668–673, 2003  相似文献   

14.
BACKGROUND: Polymer/clay (silicate) systems exhibit great promise for industrial applications due to their ability to display synergistically advanced properties with relatively small amounts of clay loads. The effects of various compatibilizers on styrene–ethylene–butylene–styrene block copolymer (SEBS)/clay nanocomposites with various amounts of clay using a melt mixing process are investigated. RESULTS: SEBS/clay nanocomposites were prepared via melt mixing. Two types of maleated compatibilizers, styrene–ethylene–butylene–styrene block copolymer grafted maleic anhydride (SEBS‐g‐MA) and polypropylene grafted maleic anhydride (PP‐g‐MA), were incorporated to improve the dispersion of various amounts of commercial organoclay (denoted as 20A). Experimental samples were analyzed using X‐ray diffraction and transmission electron microscopy. Thermal stability was enhanced through the addition of clay with or without compatibilizers. The dynamic mechanical properties and rheological properties indicated enhanced interaction for the compatibilized nanocomposites. In particular, the PP‐g‐MA compatibilized system conferred higher tensile strength or Young's modulus than the SEBS‐g‐MA compatibilized system, although SEBS‐g‐MA seemed to further expand the interlayer spacing of the clay compared with PP‐g‐MA. CONCLUSION: These unusual results suggest that the matrix properties and compatibilizer types are crucial factors in attaining the best mechanical property performance at a specific clay content. Copyright © 2007 Society of Chemical Industry  相似文献   

15.
The mechanical performance of different wood flour/polypropylene (PP) composites with interface modifications was compared. Wood flour was incorporated into the matrix after esterification with maleic anhydride (MAN) or without any modification but with the addition of a compatibilizing agent [maleic anhydride–polypropylene copolymer (PPMAN)] to modify the polymer–filler interaction. Composites were prepared by injection molding with different concentrations of wood flour. Mechanical properties (except Young's modulus) were not improved either by the wood flour chemical modification or by the use of PPMAN. However, both compatibilization methods were successful in improving the dispersion of the wood flour in the PP matrix. Creep behavior of composite samples was improved by the addition of PPMAN, whereas the composites prepared from MAN‐treated wood flour showed larger deformations than composites made with untreated particles. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1420–1428, 2003  相似文献   

16.
ABS was melt grafted with maleic anhydride at three different levels of 1, 2, and 3 wt %. These three different modified ABSs were melt blended with polycarbonate using a single‐screw extruder to choose a suitable maleic anhydride grafting level on ABS for better performance. For the compatibility study, binary blends of polycarbonate with ABS and maleic anhydride‐grafted ABS were prepared over the entire range of compositions. Compatibility of these blends was studied using a Dynamic Mechanical Analyzer and by Differential Scanning Calorimetry. Both techniques suggest more partial compatibility for modified blend systems. In addition to this, DSC thermograms show multiple peaks between the transition points of ABS fractions and polycarbonate fractions for the polycarbonate/maleic anhydride‐grafted ABS blends. These multiple peaks are characteristic of better partial compatibility with fine microstructure. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 2102–2110, 1999  相似文献   

17.
水分散型醇酸树脂的合成及性能研究   总被引:1,自引:0,他引:1  
王国建  刘洋  王丽娟 《广东化工》2007,34(1):13-16,23
以脂肪油、邻苯二甲酸酐、偏苯三酸酐和三羟甲基丙烷为主要原料合成了水分散性醇酸树脂。以原料中酸酐的比例为基础设计了合成配方,讨论了合成工艺、脂肪油的种类和比例以及醇解催化剂对水分散性醇酸树脂性能的影响。  相似文献   

18.
Highly branched polyester resins with different amounts of trimellitic anhydride (B3 monomer) and pre-polyester diol (A2 monomer) of Mesua ferrea L. seed oil, phthalic and maleic anhydrides have been synthesized. The effect of branching of the synthesized polyester resins on physical properties such as acid values, saponification values, iodine values, etc. and rheological characteristics have been studied. The extent of reaction (P) and average degree of polymerization (DP) with respect to the acid value were determined for these resinification reactions. Performance characteristics such as impact resistance, gloss, scratch hardness, chemical resistances, etc. of the cured resins have been investigated.  相似文献   

19.
Summary Monomer modified tall oil fatty acid trimethylolethane medium type of phthalic alkyds made by the High Polymer Alkyd Technique show improved properties in dry time, mar resistance, and flexibility as compared with monomer modified conventional prepared systems. Greater hardness, less color degradation, greater resistance to extended periods at high temperature, and alkali and detergent resistances result from the urea and melamine resin modifications of tall oil fatty acid High Polymer alkyds than is obtained with similarly modified conventional alkyds.  相似文献   

20.
In this work, the compatibilization of a poly(?‐caprolactone) with a number‐average molecular weight of 120,000 g/mol (PCL120) and maize starch was investigated by the addition of a chemically modified poly(?‐caprolactone). Two types of blends were prepared by melt extrusion. In type A blends, low‐molecular‐weight compatibilizers were used: (1) a poly(?‐caprolactone) with a number‐average molecular weight of 10,000 g/mol that was reacted with maleic anhydride to obtain chains terminating in carboxylic groups and (2) low‐molecular‐weight poly(?‐caprolactone)s (number‐average molecular weights of 600 and 2000 g/mol) with one pendant carboxylic group within the chains. With these groups of blends, tensile testing and scanning electron microscopy demonstrated that the compatibilizers were generally effective in inducing a better dispersion for a 60/40 poly(?‐caprolactone)/maize starch blend with a compatibilizer, improving the mechanical properties in comparison with uncompatibilized blends. The blends with 30% starch were not improved by the addition of compatibilizer, and this may be related to the rheology of the blends during preparation. In type B blends, high‐molecular‐weight compatibilizers were prepared through the grafting of variable amounts of acrylic acid or maleic anhydride to PCL120 chains. The best compatibilizer action was obtained with 0.7 wt % maleic anhydride grafted to PCL120 because both the dispersion and mechanical properties were further improved in comparison with uncompatibilized blends and type A blends. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

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