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1.
Acrylate grafted dehydrated castor oil alkyd—A binder for exterior paints   总被引:1,自引:0,他引:1  
To meet the requirement of improved durability of alkyd resin for use in weatherwork paint for superstructure of ships, an attempt has been made to chemically modify a castor oil alkyd by graft copolymerization with methyl methacrylate and butyl methacrylate in view of their ability to provide polymers with good exterior durability. Characterization of the experimental resins, in respect to physical properties, was carried out using instruments such as a vapor pressure osmometer, rotational viscometer, universal tensile testing instrument (Instron 1123), and differential scanning calorimeter. Performance of the resins was evaluated using a fluorescent UV accelerated weatherometer and multi-head glossmeter. The results reveal substantial improvement in drying and weather resistance properties of castor oil alkyd on graft copolymerization with both methyl methacrylate and butyl methacrylate. The improvement in these properties is marginally superior in the case of MMA grafted alkyds. MMA modification also enhances the mechanical properties of the grafted castor oil alkyd. Post Bag No. 10012, G.P.O., Mumbai - 400 001, India.  相似文献   

2.
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   

3.
The unique high linoleic acid content of 78% in safflower oil makes it especially suitable to the coatings industry. The high content of linoleic acid, low amount of saturated acids, and absence of linolenic acid constitutes an oil which forms fast-drying, nonyellowing films that have an excellent through dry and low wrinkling characteristics. More safflower oil is utilized in the manufacture of alkyd resins than any other single nonedible use. The oil alcoholizes rapidly with polyols and heat-bleaches to very ligh colors in cooking the alkyd resins. These alkyds have the best combination of fast-drying and nonyellowing properties of any drying oil alkyd of equal oil content. Heat-bodies safflower oil has uniform polymer structure as shown by its viscosity reduction curves. Heat-bodied and low viscosity safflower oils are used in exterior house paints. These paints show good through dry, low wrinkling and resistance to dew flatting. Specialty uses for safflower oil include urethane resins, caulks and putties, linoleum and oil emulsion exterior house paints. Presented at the AOCS Meeting, Cincinnati, October 1965.  相似文献   

4.
Short-oil alkyd resins were prepared by using five different oil types: corn oil, rice bran oil, sunflower oil, soya bean oil and dehydrated castor oil (DCO). Among these, soya bean oil gave alkyd resin with the darkest color because oxidation occurred. Auto air-dried coating films were developed and it was shown that film prepared from rice bran oil-based alkyd exhibited the longest drying time due to the low number of double bonds compared to other and the extra natural antioxidant in rice bran oil. DCO alkyd-based film revealed the shortest drying time, the greatest hardness but the poorest alkali and sea-water resistance. This is caused by the differences in the type of fatty acid and double bonds, the high amount of double bonds being in DCO. In addition, an increase in the reaction temperature only had an influence on darkening the alkyd color and decreasing the drying time of coating films. In terms of technical properties and cost competitiveness, soya bean oil-based film is the best. Coating films derived from all oil-based alkyds, except DCO, look promising for use in surfboard manufacturing.  相似文献   

5.
Alkyds prepared from castor and hydrogenated castor oils have been prepared direct from the oil and by first subjecting the oil to a glycerolysis reaction. The molecular weight distributions of the alkyds have been measured in solvent systems designed to separate predominantly on polarity and molecular weight. The properties of the alkyds in stoving enamels have been evaluated. The results are discussed in relation to existing theories relating processing conditions to molecular weight distribution in alkyd resins. Previous suggestions regarding the reactivity of the hydroxyl groups in the oil molecules are not consistent with the results obtained in this study.  相似文献   

6.
Parinari polyandra Benth seed oil was utilized in the preparation of four sets of alkyd resin (35%, 50%, 60%, and 75% oil formulations) using a two‐stage alcoholysis‐polyesterification method. The rate of polyesterification was depended on the amount of oil used during synthesis. The properties of the alkyds (drying times, film characteristics, water and acid resistances, and solubility) were evaluated using relevant standards. Inclusion of cobalt naphthenate drier in the alkyds and their exposure to outdoor temperature improved the drying properties. White gloss paints formulated from the alkyds, considering a pigment‐volume concentration of 20.67% in the gloss paint formulation compare well with commercial standard. FTIR and 1H‐NMR analysis confirm the alkyd (glycerol‐phthalate) structure. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

7.
Air drying long oil alkyd resins of 65% oil length were synthesized from a blend of soya bean (Glycine max) oil and karawila (Momordica charantia) seed oil. Different proportions of karawila seed oil (w/w% 10, 20, 30, 40 and 50) were blended with soya bean oil to examine the effect of karawila seed oil on the drying behavior of alkyds synthesized from soya bean oil. A sharp variation of viscosity is only observed for alkyd resins having more than 40% (w/w) of karawila seed oil. The polyesterification time was reduced and correspondingly the extent of polymerization was also reduced up to 30% (w/w). Significant variation in transesterification time was also observed for 30% (w/w). However, further increase in karawila seed oil above 40% (w/w) had only a marginal effect on the polyesterification reaction. The drying properties of the alkyd resins had been significantly improved with the increase of karawila seed oil up to 30% (w/w) but further increase in karawila seed oil resulted in poor drying characteristics. The film properties (drying time, hardness, adhesion, chemical resistance and gloss) of the alkyd resins were determined. The optimum film properties were recorded for the oil blend with 30% (w/w) karawila seed oil and 70% (w/w) soya bean oil.  相似文献   

8.
Two sets of alkyd resins of variable oil lengths with the required properties for offset printing ink formulations, modified by sunflower and rapeseed oil, were synthetized according to the “monoglyceride” process. The influence of the acyl composition of the modifying vegetable oil and of the oil content on alkyds’ properties was determined by detailed chemical and rheological characterization. Molecular structure, size, and molecule size distribution appeared to be linked to these two factors. A comparative study with two usual linseed oil-modified alkyds led to determination of the more appropriate alkyds for applications in offset varnishes.  相似文献   

9.
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   

10.
Waste PET bottles were depolymerized by propylene glycol at a weight ratio of PET to propylene glycol of 37.5 : 62.5, using zinc acetate as a catalyst. The glycolyzed product, consisting of oligomeric diols with a number–average molecular weight range of 240–1107, was obtained. It was further reacted with palm oil and tolylene diisocyanate to obtain urethane oils at hydroxyl to isocyanate ratios from 1 : 1 to 1 : 0.8, with and without methanol acting as a blocking agent. It was found that all the synthesized urethane oils were yellowish transparent liquids of low molecular weights. A lower isocyanate content or the presence of a blocking agent resulted in higher viscosity, higher molecular weight, and shorter drying time. The films of all synthesized urethane oils exhibited good hardness, excellent flexibility, and high impact strength. They also showed excellent water resistance, good acid resistance but only fair alkali resistance. Moreover, these prepared urethane oils had better adhesion compared with those of the commercial urethane oil. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007  相似文献   

11.
Rubber seed oil alkyd resins of 50% oil length were prepared (sample I) and parts of it modified by direct chlorination for 30 min (sample II), 60 min (sample III) and 90 min (sample IV). The concentration of the chloride ions was found to be 0.231, 0.236 and 0.239 mol/dm3 for samples II, III and IV, respectively. The IR spectra of the samples show that chlorine enters only into the aliphatic portion of the alkyd chain by addition. The physico-chemical properties and performance characteristics of the chlorinated and unchlorinated alkyd resins were determined. The results show that the chlorinated resins are fire retardant and that they possess superior drying properties, than the unchlorinated alkyds.  相似文献   

12.
Hyperbranched alkyd was synthesized by single‐step approach using trimethylolpropane, mono pentaerythritol as core material, and 2,2‐bis(methylol)propionic acid (DMPA), a combination of dehydrated castor oil fatty acid and coconut oil fatty acid as chain extender. A series of hyperbranched alkyds were prepared at different degree of branching in the alkyd structures by changing the amount of DMPA in the alkyd resin formulation. The resins were characterized by Fourier transform infrared and 1H‐nuclear magnetic resonance (NMR) spectroscopic technique. These hyperbranched alkyds were converted into polyurethane coating after reaction with hexamethylene diisocyanate trimer at a definite ratio in the presence of dibutyltin dilaurate as a catalyst. The effect of branching and polymeric chain entanglement on the glass transition temperature, Tg of the alkyd polyurethane coating (APUC) was studied by differential scanning calorimetry technique. The performance of such APUC in terms of gloss, gloss retention under accelerated QUV radiation, natural outdoor exposed condition, mechanical, and corrosion resistance properties were enhanced with the increase of polymeric chain entanglement, i.e., compactness or higher order of branching in the alkyd resin structure. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45835.  相似文献   

13.
Alkyd and styrenated alkyd resins based on fish oil and their interesterifications with linseed oil were synthesized. The various properties of fish oil, such as its iodine value, acid value, saponification value and moisture content were determined. The interesterification product of fish oil and linseed oil can be used to partially replace the commercially available linseed oil alkyd resin. Alkyd resin and styrenated alkyd resin were modified with 2,2 dimethylolpropionic acid to introduce acid functionality and then sequentially reacted with isophorone diisocyanate, neutralized with amine, chain extended with ethylenediamine and dispersed in water to form a polyurethane dispersion. The newly synthesized resins and polyurethane dispersions were studied for coating properties such as scratch hardness, adhesion, flexibility, impact, solvent and chemical resistance. The polyurethane dispersions exhibited superior coating properties to those of their respective alkyds and styrenated alkyds.  相似文献   

14.
A two-step chemoenzymatic synthesis of urethane oil, consisting of a lipase-catalyzed transesterification of castor oil with n-butanol and a reaction of the resulting precursor (partial esters) with different diisocyanates, was studied. The effect of the type of lipase, alcohol chain length, solvent, and temperature in the transesterification step was examined. Urethane oils were characterized by IR, 1H-NMR, and GPC techniques. The film properties were also tested. The composition varies with time in the transesterification step. Conversions were faster and more complete using lipozyme, where yields to 75% could be achieved. Enzyme activity increases with increase in the log P value of the solvent. The degree of transesterification and composition of the precursor have influence on the molecular weight and film properties of urethane oils. A good correlation was observed between the scratch resistance and monoglyceride percentage of the precursor of the respective urethane oils. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 69: 1451–1458, 1998  相似文献   

15.
A series of high solid alkyd polymers from soya oil fatty acid (SOFA) and dehydrated castor oil fatty acid (DCOFA) combinations with varying percentage of dipentaerythritol (DPE, a hexafunctional polyol) have been synthesized and characterized for their physicochemical, optical, thermal and mechanical properties. For the study purpose the polymers were prepared at 80% solids in mineral turpentine oil (MTO) keeping the oil length constant. The curing behavior of the alkyds was studied using FT-IR and DSC. Increasing DPE content in resin backbone was found to increase gloss and hardness. The gloss improvement was also supported well by atomic force microscopy (AFM) pictures. Results of 500 h of QUV exposure revealed higher gloss retention for DPE-based systems. When compared for the anticorrosive properties, the EIS spectrum reveals that alkyd film containing 100% DPE has the higher value of impedance.  相似文献   

16.
Rubber seed oil (RSO) was modified with different amounts of maleic anhydride, and RSO alkyds (50% oil length) were modified to various extents by the incorporation of different amounts of maleic anhydride and fumaric acid. All the resins were evaluated as water‐reducible binders. Modification with maleic anhydride increased the acid and saponification values of RSO but reduced the iodine value. RSO modified with maleic anhydride exhibited lower amounts of volatile organic compounds (<20 g/L) than the corresponding RSO alkyds (34–87 g/L). The alkyd samples were superior to the modified RSO in chemical resistance. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3256–3259, 2003  相似文献   

17.
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   

18.
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   

19.
Summary The preparation and properties of two series of castor oil urethane foams, one from castor oil and the other from elaidinized castor oil, were investigated. The first series of foams was made from prepolymers containing 60% of castor oil prepared at increasing temperature levels to vary the degree of crosslinking in the final foams. These foams had lower tensile strengths than observed for a previously prepared foam of 60% castor oil and did not show significant differences in water resistance as crosslinking varied. They were increased nearly 100% in compressive strength with increased crosslinking and had very good shrinkage characteristics as values of only 1 to 2% were obtained. A second series of foams was prepared from 50, 60, 70, and 80% of elaidinized castor oil to compare with foams from a similar series from castor oil. This series of foams of 50 to 80% elaidinized castor oil contents was similar in density (1.7 to 6.7 lbs./cu. ft.), had improved shrinkage characteristics (11, 1, 3, and 4%, respectively), showed increased compressive and tensile strengths (up to 12.1 p.s.i. at 50% compression modulus and 34.7 p.s.i. ultimate tensile for the 60% foam formulation), and had better water-resistance properties (411 to 155%vs. 515 to 170% water absorption) than the analogous foams from castor oil. In general, humid aging only slightly affected the values obtained for the foams and was significant in only a few instances,e.g., decreased tensile in the elaidinized castor oil series. Thus increasing crosslinks in the foam apparently did not improve water resistance but did improve shrinkage characteristics in addition to some increased strength properties, as would be anticipated. Foams from elaidinized castor oil, while similar in density and foaming characteristics to analogous foams from castor oil, exhibited less shrinkage and improved water-resistance. Presented at the 50th Annual Meeting of the American Oil Chemists' Society, New Orleans, La., April 20–22, 1959. Ono of the laboratories of the Southern Utilization Research and Development Division, Agricultural Research Service, U. S. Department of Agriculture.  相似文献   

20.
In this research hyperbranched resins containing fatty acid residues were synthesized. Dipentaerythritol which has six hydroxyl groups was used as the core molecule, and it was transesterified with (i) castor oil, and (ii) a mixture of castor oil and linseed oil at 240 °C. The resulting molecule had hydroxyl containing ricinoleic acid residue coming from castor oil. It was then esterified with dimethylol propionic acid at 140 °C in the presence of para-toluene sulfonic acid used as catalyst. The hyperbranched resin thus produced was then mixed with melamine-formaldehyde resin to improve its properties. The resins were characterized by FTIR spectroscopy, and the thermal properties were determined by DSC. The resins were thermally stable up to 316 °C. The viscosity of the resin that was synthesized by using only castor oil was 3.0 Pa s, while the one synthesized by using 50% linseed oil had a viscosity of 1.0 Pa s. When reacted with dimethylol propionic acid the viscosity of the former resin increased to 7.0 Pa s, and that of the second to 3.7 Pa s. The hyperbranched resins showed excellent adhesion, gloss, flexibility, and formability. The mixed resin (i.e. hyperbranched and melamine-formaldehyde) had higher hardness values but lower gloss, adhesion, and bending resistance. Both types of resins also had good impact and abrasion resistances.  相似文献   

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