Manufacture of Alkyd Resin from Castor Oil
←
→
Page content transcription
If your browser does not render page correctly, please read the page content below
World Academy of Science, Engineering and Technology 48 2008 Manufacture of Alkyd Resin from Castor Oil Nway Nay Hlaing1, Mya Mya Oo2 endless use of the article of manufacture. The industrial Abstract— Oil-modified alkyd resin was prepared from finishes include primers and top coats for refrigerators, crude castor oil. The experiment started with investigating the furniture, and electrical equipment. In view of the optimum conditions for neutralization of crude castor oil and development of these items and sectors, the positive growth is bleaching of neutralized oil. Then the characteristics (iodine expected for paint industry [2]. value, viscosity, acid value, refractive index and color) of oils Further the paint industry envisages a future were determined. Refined oil has iodine value of 90, expansion in view of development in Automobile Industry, kinemetic viscosity of 4 St, free fatty acid value of 1, utility in Nuclear Power Station, development in Corrosion refractive index of 1.474 and color number of 8. These results Resistant Coatings, expansion in housing activity and other showed that the refined oil was qualified to prepare industry uses. The demand of alkyd resin being an ingredient dehydrated castor oil. Dehydration of refined oil was carried in Paint, Varnish and Printing ink industry would be linked out at 210-220˚C under 600-640mmHg with the help of 1% with the Paint industry. (wt%) NaHSO4 catalyst. The dehydrated castor oils were There are many significant efforts that have been analyzed for iodine value, viscosity and its set to touch time made to increase alkyd resin production. Many researchers and drying time were also investigated. Dehydrated castor oil have attempted to search the different sources for alkyd resin has iodine value of 140, kinemetic viscosity of 1.6 St, set to preparation. Airegumen I Aigbodion et al [3] studied touch time of 4 hr and drying time of 5 days. And then , oil enhancing the quality of alkyd resins using methyl esters of modified alkyd resin (acid value 6.6) was prepared from rubber seed oil in 2004. dehydrated castor oil by alcoholysis method in excess of A lot of alkyd resins were imported to Myanmar glycerol and phthalic anhydride in the presence of 0.3% (wt%) Paint Industries every year. In order to save foreign currency NaOH catalyst. The obtained resin was characterized by outflow, it is needed to produce alkyd resin in Myanmar. Fourier Transform Infrared Spectrophotometer (FTIR) and the The oils that are mostly employed for alkyd resin properties were determined. synthesis are linseed oil, soybean oil, dehydrated castor oil, fish oil and tall oil. Myanmar being rich in aquatic and terrestrial resources, every state and division is pursuing the Keywords— Alcoholysis method, Alkyd resin, Castor oil, target of putting 500,000 acres under physic nut (castor oil) in Dehydrated castor oil, Polymerization three years. Rural development tasks are included in the national development endeavors that are being carried out by I. INTRODUCTION the Nation target. Polymerization is one of the most important Castor oil is useful directly in protective coatings as a industrial processes. Resins and emulsion are two main classes plasticizer in alkyd systems, and blown castor oil is an of polymer. Alkyd resins are by far the most important class important nitrocellulose plasticizer. In commercial of coating resins. It is estimated that alkyd resins contribute manufacture of dehydrated castor oil, the aim is to produce the about 70% to the conventional binders used in surface coating most valuable material for use as a drying oil. By far the most today. The popularity of alky resins as vehicle for coatings is important coatings use of castor oil is in the form of largely due to their unique properties such as film hardness, dehydrated castor. Dehydrated castor oil is now recognized as durability gloss and gloss retention, resistance to abrasion, etc. an individual drying oil with its own characteristic properties impacted on them through modification with drying oil [1]. and advantages. The drying oils owe their value as raw Alkyd resins are used in both clear and pigmented, materials for decorative and protective coatings to their ability industrial and trade coating to protect and decorate a wide to polymerize or “dry” after they have been applied to a variety of substances. The industrial coatings or finishes surface to form tough, adherent, impervious, and abrasion generally are applied during the manufacturing process of the resistance films. The advantages claimed in surface coating item which they cover. Often they are specifically formulated applications include excellent odor and heat bleachability, to meet both conditions desired for their application and the good drying properties, more uniform polymer structure, and lack of after-yellowing. The dehydrated castor oil is non- yellowing oil and so this can give requirements of coating 1.Department of Chemical Engineering, Mandalay technological industries [2,4,5,6,7]. University, Patheingyi Township, Mandalay, Myanmar, Myanmar 11011, e- mail: nway.nay5@gmail.com 2.Yangon Technological University, Gyongone, Insein, Yangon, Myanmar 2. Materials and Methods 11011, e-mail : most7@gmail.com 2.1. Neutralization of Crude Castor Oil 155
World Academy of Science, Engineering and Technology 48 2008 Oil (100g) was heated to 55˚C. Then, the calculated amount of strong (45˚Be, 2N NaOH) lye was added to neutralize the free fatty acids exactly, with constant stirring. Completion of neutralization reaction was determined by testing the mixture with phenolphthalein indicator. When the indicator color of the sample mixture turned to pink, neutralization was completed. Then NaCl solution was heated to 90˚C and 20ml of hot NaCl solution was added to the Figure 2.1.Dehydration of Castor Oil mixture to ensure adequate salting or graining out of soapstock. After that the mixture was poured into separating 2.4. Preparation of Alkyd Resin funnel. Three hours later, the mixture was separated into two Oil modified alkyd resin was prepared with distinct layers. Then the lower layer or soap layer was drain dehydrated castor oil, glycerol and phthalic anhydride using out. The upper layer or oil layer was washed with hot water. NaOH catalyst. The preparation was done in a 4-neck round Washing was carried out until color of phenolphthalein bottom flask fitted with a motorized stirrer, a nitrogen inlet, a indicator did not change to pink. After complete washing, the thermometer pocked and a hold for sampling. The system was oil was dried at 100˚C in oven to evaporate the moisture. shown in Fig. 2. In the preparation of alkyd resin, two stages Drying and cooling was carried out until the weight of dried were involved. The first stage was alcoholysis stage and the oil remained unchanged. second stage was esterification stage. The neutralized oils were weighed to calculate oil Raw material Weight (g) Weight (%) loss and then their free fatty acid content (FFA) were Dehydrate castor oil 114.27 60.437 determined [8]. The characteristics of crude oil and (DCO) neutralized oil were determined by American Society of Phthalic anhydride (PA) 43.364 22.935 Testing and Materials (ASTM) standard methods. Glycerol (G) 31.44 16.63 Total 189.074 100 2.2. Bleaching of Neutralized Oil The neutralized oils were heated to 100˚C and different Stage 1 (alcoholysis): In this stage, monoglyceride was first amounts of activated charcoal were added. After the mixture prepared by reacting the oil with glycerol. Alcoholysis of oil was stirred for 45 minutes, the mixture was cooled to room was carried out with different percentages of (0.03%, 0.05%, temperature and activated charcoal was removed by filtering 0.1%) (by weight) PbO catalyst and (0.1%, 0.2%, 0.3%)(by with filter paper. weight) NaOH catalysts. The neutralized oils were also bleached with different In alcoholysis reaction, the oil was heated with amounts of bentonite and a mixture of activated charcoal and agitation speed of (700 rpm) and N2 sparging rate of about bentonite (1:1 ratio). Then the process was carried out above (0.06ft3/sec) to 230-240˚C. Glycerol and selected catalyst was procedure. added and alcoholysis reaction was carried out at 230-240˚C. The colors of bleached oil samples were determined The reaction was continued until a sample of the reaction by a spectrophotometric method [11]. In this method, optical mixture became soluble in two to four volumes of anhydrous densities were measured at the wavelength of 460nm, 550nm, methanol. After alcoholysis reaction was completed, the 620nm and 670nm. Then the photometric colors were reaction mixture was cooled to 140˚C. calculated by the following equation. Stage 2 (esterification): In this stage, phthalic anhydride was Photometric color = 1.29D460 + 69.7D550 + 41.2D650 – added to the monoglyceride mixture. The temperature was 56.4D670 [4] maintained at the range of 230-240˚C and maintained at this temperature. The sparging rate of N2 was increased to 2.3. Dehydration of Castor Oil (0.1ft3/sec). The reaction was monitored by periodic determination of the acid value of the mixture until acid value Bleached oil (50g) and 2% (wt%) of NaHSO4 catalyst were dropped to nearly 5. placed into round bottom flask and the apparatus was set up as The acid value of alkyd resin was determined by ASTM D shown in figure (1). The system was heated to 210-220˚C for 1639-90 and the chemical resistances also determined. The dehydration time were taken for 15, 30, 45, 60, 75 minutes. prepared resin was standardized by FTIR [12, 13]. Dehydration was also carried out under 600-640 mmHg (vacuum) as described in the above process. In this process, the effect of NaHSO4 catalyst amount on the properties of dehydrated castor oil was also investigated. Then, the iodine values of dehydrated castor oil were determined by ASTM D1541-86 and viscosities were determined by ASTM D 1545-63 method. The drying time and set to touch time were also determined by ASTM D 1953- 70 [9]. Fig.3.3.Alkyd Resin Preparation 156
World Academy of Science, Engineering and Technology 48 2008 Bleaching time = 45 minutes 3. Results and Discussion *Photometric color = 1.29D460 + 69.7D620 + 41.2D650 í 3.1. Results Sample Bleaching (wt%) of Photometric Wt. of 3.1.1. Characterization of Crude Castor Oil no. agents bleachin color Refined oil The characteristics of crude castor oil are shown in g agent number (g) Table 3.1. A1 Activated 3 7.25 57.437 Table 3.1. The Characteristics of Crude Castor Oil A2 charcoal 5 6.35 57.400 Characteristics Crude castor oil A3 (A) 7 7.16 57.36 Free fatty acid value 19 A4 9 8.32 57.254 A5 11 9.29 57.217 Color, photometric - B1 Bentonite 3 3.80 58.118 Refractive index - B2 (B) 5 3.40 57.386 B3 7 4.40 57.380 Specific gravity 0.9633 B4 9 4.47 57.311 Viscosity(Stroke) 4.5 C1 Activated 3 4.0 57.405 C2 charcoal 5 3.0 57.342 Iodine value, wiji’s 89.5 C3 and 7 4.46 57.254 bentonite 3.1.2. Neutralization of Crude Castor Oil (1:1 ratio) Table 3.2 show the FFA content of neutralized oil. (C) Initial weight of crude castor oil = 100g 56.4D670 [4]. FFA (%) of crude oil = 19% Neutralization temperature = 55˚C 3.1.5. Dehydration of Refined Castor Oil 20% NaCL solution = 40ml Table 3.5 present the yield of dehydrated castor oil at Sr. 2N Neutralization FFA (%) Weight of different dehydration conditions. The changes of iodine value no NaOH time(minutes) of Neutralized and viscosity by dehydration of castor oil at different Neutralized oil (g) dehydration conditions are shown in Fig. 3.1 and Fig. 3.2. oil 1 15.2 5 8.448 65.09 Table 3.5. Yield of Dehydrated Castor Oil at Different 2 30 10 0.987 60.43 Dehydration Conditions Initial weight of sample C2 = 50g 3 30 10 0.988 51.79 4.1.3. Characterization of Refined Castor Oil The characteristics of refined castor are described in Table 3.3 by comparing with ASTM standard castor oil. Table 3.3.Characteristics of Refined Castor Oil Characteristics Refined Castor oil castor oil (ASTM D 960-79) Free fatty acid value 1 1.00 Color, photometric 8 - Refractive index 1.474 1.476 to 1.4778 Specific gravity 0.9614 0.957 to 0.961 Viscosity(Stroke) 4 6.3 to 8.9 Iodine value, wiji’s 90 83 to 88 Source [6] 3.1.4. Bleaching of Neutralized Castor Oil Effect of bleaching on color and yield of neutralized castor oil is shown in Table 3.4. Oil was bleached with 0-11% of activated carbon, 0-9% of bentonite and 0-7% of 1:1 mixture of activated charcoal and bentonite Table 3.4. Effect of Bleaching On Color and Yield of Neutralized Castor Oil Initial weight of neutralized oil = 100 g Bleaching temperature = 100˚C 157
World Academy of Science, Engineering and Technology 48 2008 NaHSO4 V.P Dehydration time (minutes)/Yield (%) catalyst (mm (%) Hg) 15 30 45 60 75 um ) 2 760 0.5 90.37 89.88 89.56 89.55 cu , va m Hg 140 0m 2 600- 90.9 90.11 89.5 89.13 89.06 -6 4 (60 0 u m) 640 5 acu 135 O HS 4 ,v Na Hg 130 2% 0 mm 1 600- 90.2 90.035 89.67 89.39 89.28 0 -6 4 125 (60 SO 4 640 Iodine Value H Na 120 1% 115 1 110 ho ut vac uu m) dehydration with 1% NaHSO4 catalyst for 60 minutes S O 4(w it 2 2 % N aH dehydration with 2% NaHSO4 catalyst for 45 minutes 105 100 3.1.7. Preparation of Alkyd Resin Reaction condition of alcoholysis reaction condition 10 20 30 40 50 60 70 80 Dehydration Time(min) in alkyd resin preparation is described in Table 3.7. Fig. 3.3 shows the acid value control of esterification reaction. Yield of dehydrated castor oil-modified alkyd resin and the Fig. 3.1.Change of Iodine Value with Reaction Time calculation for percentage of reaction complection are for Dehydration Temperature at 210-220˚C presented in Table 3.8. The appearances of gel type resin, dehydrated castor oil-modified alkyd resin are shown in Fig. 3.4. Table 3.7. 1st Stage Alcoholysis Reaction Conditions Reaction temperature = 230-240˚C 2% Na Agitation speed = 500 rpm = 0.06 ft3/minutes 4 .6 4 .4 HS O 4 (w it h N2 sparging rate 4 .2 ou 4 .0 tv ac uu Alcoholysi Catalyst Reaction Completion of 3 .8 m 3 .6 ) s catalysts % (wt%) time (hr) alcoholysis Viscosity(Stroke) 3 .4 3 .2 2% N reaction* 3 .0 aH 1% 2 .8 SO 4 (6 00 Na HS PbO 0.03 4 Not complete -6 O (6 2 .6 2 .4 40 m 4 00 -6 40 0.05 4 Not complete m m 2 .2 2 .0 Hg ,v m Hg ,v 0.1 4 Not complete a cu ac 1 .8 1 .6 um ) uu m ) NaOH 0.1 4 Not complete 1 .4 10 20 30 40 50 60 70 80 0.2 4 Not complete D e h y d r a t io n T im e ( m in ) 0.3 2 complete *It was determined by testing the solubility of alcoholysis Fig.3.2. Change of Viscosity with Reaction Time mixture in anhydrous methanol. for Dehydration Temperature at 210-220˚C 4.1.6. Characterization of Dehydrated Castor Oils 100 The characteristics of typical dehydrated castor were presented in Table 3.6 by comparing with ASTM standard acid value dehydrated castor oil. 10 Table 3.6.Characteristics of Typical Dehydrated Castor Oils Vacuum pressure = 600-640 mmHg Characteristics Dehydrated Dehydrated Standard 1 castor oil1 castor oil 2 dehydrated 30 60 90 120 150 castor oil (ASTM reaction time (minutes) D961-86) Iodine value 140.01 139.05 125-145 Fig.3.3. Acid Value Control of Esterification Reaction Viscosity 1.600 1.686 1.5-1.8 Table 3.8. Yield of Dehydrated Castor Oil-Modified Alkyd (Stroke) Resin Set to touch 4 3.5 2.5,approxi time (hour) mately Drying time 5 5 - (hour) 158
World Academy of Science, Engineering and Technology 48 2008 I.W-initial weight DCO I..W(g) F.W Y IAV FAV P F.W-final weight alkyd (g) (%) (%) Y-yield resin IAV-initial acid value (100% 6.6 97.72 FVA-final acid value solid) 189.58 140 73.85 298.58 P-degree of reaction complection 2 8 5 1125.26 1150-1060 O=C-O-C- 3.1.8. Characterization of Alkyd Resin The physico-chemical properties of alkyd resin are presented in Table 3.9. The chemical resistances of alkyd resin film are shown in Table 3.10. Table 3.11 show FTIR absorption band of dehydrated castor oil-modified alkyd resin. 3.2. Discussion 3.2.1. Discussion on Characteristics of Crude Castor Oil Table 3.9. Characteristics of Dehydrated Castor Oil-modified According to Table 4.1 FFA content of crude castor oil Alkyd Resin was high and it was not within the ASTM specification limit. Properties DCO RSO alkyd DCO The color and refractive index of crude oil can not be alkyd resin* alkyd determined because the transparency of crude oil was very resin resin poor. The viscosity of crude oil was slightly lower than that of Acid value 6.6 12.7 4-11 ASTM standard oil [6]. Even though, the specific gravity and Iodine 80.24 66.3 - iodine value of crude oil were in the range of ASTM value specification limit, the FFA content of crude oil was differed Color Yellow Brown - from ASTM standard. The only reason to reduce the FFA Refractive 1.477 1.5050 - content of oil was to neutralize the crude oil. index Gouge HB HB - 4.2.2. Discussion on Neutralization of Crude Castor Oil hardness In neutralization process, it was found that 30 ml of 2 Scratch F H - N NaOH per 100g of oil was required to obtain neutralized oil hardness with an acceptable FFA content and to be a minimum of oil RSO- rubber seed oil loss. The neutralization time of 10 minutes was sufficient to Source [1, 14] reduce FFA content from 19% to 1%. In neutralization of oil, free fatty acid content of oil was converted in oil soluble Table 3.10. Chemical Resistances of Alkyd Resin Films soaps. Small amount of impurities such as phosphotides, Media Immersion Appearance of proteins or protein fragments, and gummy or mucilaginous time (hours) film* substances were also removed by neutralization process. Therefore, the initial weight of oil was decreased as well as Distilled water 18 Not effect the yield of oil was decreased. In neutralization process, there 8 Whitening was a difficulty to separate the soap and oil layer because FFA 3 N NaOH 16 Blistering content in crude oil was very high. The two layers can be 24 Removal easily separated when NaCL solution was added to the *It was examined after the films were air dried for 30 minutes. neutralized mixture because NaCL can help to ensure adequate salting or graining out of the soapstock. Other Table 3.11. FTIR Absorption Band of Dehydrated Castor Oil- impurities in oil were removed by washing with hot water. In Modified Alkyd Resin washing step, there has a little loss of oil. So, the average Band Experimental Literature Remark yield of oil was 64%. No. frequency frequency (cm-1) (cm-1) 3.2.3. Discussion on Characteristic of Neutralized Castor Oil 1 3008.99 Near 3030 =C-H From Table 3.3., it can be seen that the neutralization 2926.74 process can reduce the FFA content of crude oil from 19% to 2 3514.21 3570-3200 O-H 1%. Then, it can give the refined oil color of 8 and refractive 1169.21 Near 1100 O-H index of 1.474. Therefore, neutralization process can offer 3 2855.67 2926-2850 C-H great effect on FFA content, color and refractive index of oil. 1460.43 1485-1440 CH2 Moreover, the refined oil has specific gravity of 0.9614, 4 1738.64 1750-1735 CH3COOCH3 viscosity of 4 and iodine value of 90. These results were nearly the same as that of the crude oil. Although the 1730.30 1730-1717 COO neutralization technique reduced significantly FFA content in 159
World Academy of Science, Engineering and Technology 48 2008 oil, it gave slightly effect on specific gravity, viscosity and 4.2.6. Discussion on Characteristics of Dehydrated Castor Oils iodine value of oil. The iodine value and viscosity control the extent of reaction and set to touch time and drying time show the drying 3.2.4. Discussion on bleaching of neutralized oil properties of dehydrated castor oil. Table 4.7 described that In Table 3.4, it can be seen that the highest color removal the iodine value and viscosity of dehydrated castor oils were efficiency was obtained by bleaching with 5% of bleaching in the limit of ASTM standard dehydrated castor oil. Then the agents. 5% of activated carbon, 5% of bentonite and 5% of drying time and set to touch time also gave satisfactory result. (1:1) mixture of activated charcoal and bentonite can give the Therefore, these dehydrated castor oils were acceptable to oil with photometric color of 6.35, 3.4 and 3.0 respectively. prepare drying oil-modified alkyd resin. Bleaching with (1:1) mixture of activated charcoal and 4.2.7. Discussion on Preparation of Alkyd Resin bentonite can offer better result. So, it can be chosen as According to the literature [3], the alcoholysis bleaching agents in bleaching of neutralized oil. reaction is usually completed within an hr or two hrs after the Beside decoloring, bleaching of neutralized oil served the batch had reached operating temperature. In Table 4.8, it was important function of largely removal of trace amount of soap. found that the samples of the alcoholysis mixture did not After bleaching process, the average oil yield was 69%. The completely soluble in anhydrous methanol although the oil yield was decreased during the bleaching process due to alcoholysis reactions were carried out for 4hr by using the adsorption of oil on the surface of adsorbents and the different amount of litharge catalysts (0.03%, 0.05%, 0.1%) filtration of oil with filter paper. and NaOH catalysts (0.1%, 0.2%). It should not be tried to use the amount of PbO catalyst more than 0.1% (wt%) because the 4.2.5. Discussion on Dehydration of Castor Oil preferred PbO catalyst percent for alcoholysis reaction is 0.01- According to the Table 3.5, the yield of dehydrated 0.1 in literature. Then, large quantities of catalyst lead to dark castor oil decreased with increasing the dehydration time. the color of alkyd resin and detract from the water and alkali Then, there was a slightly different in yield of dehydrated resistances of alkyd resin. In alcoholysis of oil with 0.1% castor oil although the dehydration process was carried out (wt%) and 0.2% (wt%) NaOH catalyst, it cannot also give different dehydration conditions. complete alcoholysis mixture after reaction was carried out for In Fig. 3.1 and 3.2, it was observed that the 2 hrs. The degree of alcoholysis has an important bearing on dehydrated castor oil with a maximum iodine value and a the properties of the resulting resin. During the final reaction minimum viscosity could be obtained at the proper reaction with phthalic anhydride, esterification of the free hydroxyl time. The iodine values of dehydrated castor oil increased groups of the monoglyceride must compete with any with the reaction time and reached a maximum value. Then, it unreacted or excess glycerol. The latter reaction leads to decreased because prolong heating leads to polymerization glyceryl phthalate which is insoluble in the oil-acid-glyceryl with a consequence drop in iodine value and a step rise in phthalate and unreacted glyceride oil. Unless sufficient viscosity. The minimum viscosity occurs at or near the point monoglyceride is present prior to the addition of the phthalic of maximum iodine value. anhydride, the reaction product will be unsoluble gel of From Fig. 3.1, the dehydration of oil without vacuum glyceryl phthalate suspended in oily mixed glycerides. Such a system could not give acceptable iodine value to qualify as product is worthless. drying oil because the iodine value of oil was below 125 (the In esterification reaction, it was observed that the lower limit of ASTM dehydrated castor oil) . In this process, a longer the reaction time, the more viscous the mixture is. In lot of fumes were evolved during dehydration of oil and these this stage, adequate agitation was necessary for complete fumes were condensed and dripped back into the dehydrated mixing of monoglyceride mixture and phthalic anhydride. oil. It was undesirable effect. Therefore, it is required to use a Unless adequate mixing was supplied in this stage, the current of inert gas such as carbon dioxide or nitrogen in order unqualify alkyd resin would be resulted. So, the N2 sparging to remove the decomposition products. The most effective rate was increased in order to remove liberated reaction way of removing of fume is by using the vacuum pressure. By product and to increase the heat and mass transfer of chemical this means, the problem of condensing the fume into the reaction. In Fig. 3.3, the oil-modified alkyd resin with acid dehydrated oil was largely avoided. Therefore, dehydration of number of 6.6 was obtained after the esterification reaction refined castor oil was carried out under vacuum system. was carried out for 150 minutes. It should not try to proceed When dehydration of oil was done by using 1% of NaHSO4 the reaction after the acid number of alkyd resin had dropped catalyst and vacuum pressure of 600-640 mmHg and the to 6.6 because the reaction was closed to gel point. optimum reaction time is 60 minutes, this system could give In Table 3.8, it was observed that 97.72 % of reaction dehydrated castor oil with iodine value of 140. When was completed when the final acid number of alkyd resin was dehydration of oil was done by using 2% of catalyst and 6.6. Then, the yield of alkyd resin was 73.87%. vacuum pressure of 600-640 mmHg and the optimum reaction time is 45 minutes, this system could give the dehydrated 3.2.8. Discussion on Characteristics of Alkyd Resin castor oil with iodine value of 139.05. Although the In Table 3.9, there is no common standard to compare dehydration time was decreased with increasing the amount of alkyds resins. Each alkyd resin has its own properties. The catalyst percent, the refractive index of the dehydrated oil was alkyd resin that has acid number of less than 15 is suitable for increased. application of paint, according to literature [1, 7, 8]. The scratch hardness of alkyd resin was F and gouge hardness was 160
World Academy of Science, Engineering and Technology 48 2008 HB. The refractive index of alkyd resin was 1.447 and color was yellow. [1]Patton, T.C. 1962. Alkyd Resin Technology. NewYork: 4.2.9. Discussion on Chemical Resistance of Alkyd Resin Interscience Publishers, Inc. A Division of John Wiley and Film Sons, Inc. The resistance of alkyd film was determined in two media, distilled water and NaOH solution. Table 3.10 described that [2] Waters, R.T. Resins-Synthetic, Alkyd Resins. Section 2. there was no effect on alkyd film after immersion in distilled London: Wyman and Sons, Ltd. 1955. water for 18 hours. The immersion of alkyd film in water for 18 hours was sufficient time to examine the water resistance. [3] Ikhuoria, E.U., Aigbodion, A.I., and Okieimen, F.E. When the alkyd film was immersed in strong alkali solution, “Enhancing the quality of Alkyd Resins Using Methyl Esters 3N NaOH, the film got whitening after immersion time for 8 of Rubber Seed Oil”. Tropical Journal of Pharmaceutical hours, blistering after immersion time for 16 hours and Research. 3 (No.1): 2004, 311-317. removal after immersion time for 24 hours. So, these results show that the prepared alkyd resin has high chemical [4] Formo, M.W. et al. Bailey’s Industrial Fats and Oils resistance. Products. Vol 1. 4th Edition. New York: John Wiley and Sons, Inc, 1965. 4.2.10. Discussion on FTIR Adsorption of Dehydrated Castor Oil-Modified Alkyd Resin [5] Kirk, R.F and Othmer, D.F. Alkyd Resin: Encyclopedia The FTIR spectrum of prepared alkyd resin exhibits a of Chemical Technology. Vol 9. New York: John Wiley and characteristic of straight chain ester band at 1738.64 cm-1 and Sons, Inc, 1947. aromatic ring ester band at 1730.09 cm-1. The present of O=C- O-C- also exhibit a characteristic ester band at 1125.26 cm-1. The appearance of CH2, -CH- confirms the present of methyl [6] Mark, H.F. Alkyd Resin: Encyclopedia of Polymer group at 1460.43 cm-1 and 2856.67 cm-1. The adsorption band Science and Technology. Volume 1. New York: Interscience at 3008.99 cm-1 is characteristic of alkene carbon (=C-H) Publishers. A Division of John Wiley and Sons, Inc, 1964. according to literature [12, 13]. [7] Mark, H., Proskauer, E.S., and Frilette, V.J. Resins, 4. Conclusion Rubbers, Plastics Yearbook. New York: Interscience The characteristics of refined castor oils were found Publishers, Inc. A Division of John Wiley and Sons, Inc, to be standardized with ASTM standard castor oils and it was 1954. suitable to carry out the next step. The refined castor oil was done by using NaHSO4 catalyst to carry out the dehydration [8] Mehlenbacher, V.C. Official and Tentative Methods for process. Dehydration under vacuum pressure system was the American Oil Chemists’ Society. Second Edition. effective processing method and this pressure influenced the American Oil Chemists’ Society (AOCS). Chicago: 35 East quality of dehydrated castor oil. A typical dehydrated castor Wacker Drive, 1950. oil (iodine value 140, viscosity 1.6 stroke, set to touch time 3.5 hr and drying time 5 day) was prepared with 1% NaHSO4 [9] Anonymous. Annual Book of American Society for catalyst under vacuum of 600-640 mmHg at 210-220˚C. In Testing and Materials (ASTM). Part 27, 1975.28, 29. USA. alcoholysis of oil by using 0.3% (wt%) NaOH catalyst, it gave . complete alcoholohysis mixture to preceed the esterification reaction after reaction time for 2 hrs. Dehydrated castor oil [10] Pecsok, R.L. Methods of Chemical Analysis. Second has been used in the preparation alkyd resin. Dehydrated Edition. New York: Interscience Publishers, Inc. John Wiley castor oil-modified alkyd resin (acid value 6.6) was prepared and Sons, Inc, 1980. by alcoholysis method from dehydrated castor oil, glycerol and phthalic anhydride with a help of 0.3% NaOH catalyst. [11] Branch, R.F. Application of Infraced and Ultraviolet The physico-chemical properties and high chemical resistance Spectra to Organic Chemistry: Practical Organic Chemistry, of alkyd resin film showed that they were promising in 1946. formulating of paint. [12] Grasselli, J.G., Mocadlo, S.E., and Mooney, J.R. Acknowledgements Applied Polymer Analysis and Characterization, Analysis The financial support of Ministry of Science and of Polymers by Fourier Transform Infrared Spectroscopy. Technology is gratefully acknowledged. The author wishs to Vol. 2. New York: Oxford University Press. extend her gratitude to Prof. Dr. Mya Mya Oo for stimulating discussion. [13] Sanler, S.R. et al. Polymer Synthesis and Characterization. A Laboratory Manual. USA: Academic Press. A Division of Harcourt Brace and Company, REFERENCES California, 1998. 161
You can also read