Surveies on the Physico-chemical belongingss of hura crepitans seed oil and its alteration have been carried out. Properties such as coloring material, specific gravitation, % free fatty acid, acerb value, saponification value and iodine value were determined. Hura Crepitan seed oil based alkyd rosins were antecedently prepared by step-wise polymerisation of the monoglycerides with phthalic anhydride. Properties of movie samples prepared from the alkyd rosins were evaluated as composite binders for surface coatings. The movie samples were of comparatively lower volatile organic compound ( VOC ) ( between 0.2 and 0.9 % ) compared to their corresponding alkyd rosins ( about 1.3 % ) . The composite binder exhibited first-class opposition to brine and H2O, and just opposition to acid and alkali.
KEYWORDS: Hura Crepitans ; Volatile organic compounds ; Alkyd rosin, movie belongingss
Alkyd rosins have proven themselves both from a cost and public presentation point of position over a broad scope of coatings applications for architectural metal, wood, industrial, agricultural and building equipments, Patton, ( 1962 ) , Ikhuoria et Al, ( 2004 ) . As alkyd coatings are solvent-borne, they contribute to Volatile Organic Compounds ( VOC ) emanations. Increasing concerns sing land degree ozone and indoor air quality have spurred research activities to happen alternate engineerings to take down VOC emanations without compromising public presentation, Waters, ( 1955 ) . This has proven to be a major challenge for the coating industry as the cardinal issue is redeveloping solvent borne coatings holding lowest possible VOC while presenting expected public presentation benchmarks. Planing alkyd rosin composite binder for surface coating and low VOCs solvent- Borne alkyds are a few constructs which can be used for a sustainable and environment friendly coatings without giving their public presentations, Kirk, R.F and Othmer, ( 1947 ) . The possibility to obtain various, low cost, renewable, and low VOC emanation merchandises makes alkyd movies really attractive stuffs, Aigbodion et Al ( 2003 ) .VOC compliant coatings can be met through minimising the dissolver content to do high solids rosins or by emulsifying the alkyd into H2O to do alkyd emulsions. Alkyds and acrylics can be combined by emulsification to do the so called intercrossed movie formers, Kent et Al, ( 2008 ) . In this present survey, the movie belongingss of oil-modified alkyd rosin prepared with oil obtained from Hura crepitans seed oil and blends of the alkyd and poly vinyl ethanoate achieved utilizing additive alkyl benzine sulphonate as emulsifier are presented.
MATERIALS AND METHODS
Technical classs phthalic anhydride, glycerin, xylene, iodine trichloride and other reagents were used in chemical procedures and word picture were supplied by British Drug House ( BDH ) , Poole, England.
Word picture of the oil and Preparation of Alkyd Resin
The word picture of the oil and alkyd rosin readying were reported in old work, Idiaghe, Imanah and Bakare, ( 2005 ) .
Word picture of the Alkyd Resin
Physico-chemical belongingss of the alkyd rosin were determined in comparing with the virgin Hura Crepitan seed oil. The drying agenda and the opposition of the alkyd sample in different service media were evaluated utilizing standard methods ; ASTM D1640-69 and ASTM D1308-5-57 severally.
Preparation of the Hybrid Binder
The intercrossed binder was prepared harmonizing to the method described by Aigbodion et Al, ( 2003 ) : A supersaturated solution of the alkyd rosin in xylene was prepared and parts were taken for farther reaction harmonizing to the preparation in Table. 1. Polyvinyl ethanoate ( 70 % , w/w ) and 1ml of x % solution of additive alkyl benzine sulphonate ( surfactant ) were added, while being smartly stirred. Cobalt and Ca desiccants were added to the binders. Each alkyd-poly vinyl ethanoate intercrossed binder sample was applied on a glass home base and oven-baked for about 90 min at 100oC. A control sample ( alkyd rosin entirely ) was likewise treated. The chemical opposition of the movies was determined following ASTM 9D1308-57 standard trial method.
RESULTS AND DISCUSSION
Word picture of the Alkyd Resin
The alkyd rosin features presented in Table 2, revealed that the denseness of the rosin under the same status of temperature is somewhat higher than the natural oil. The high saponification value of the rosin could be due to the predomination of the ester linkages in the rosin chemical construction, Kihlefer, ( 1938 ) . The few proportion of the unsaturated fatty acid from the oil nowadays in the rosin could be the ground for the low I value of the rosin in comparing with the oil.
The chemical opposition of the alkyd rosin movie in different service media is presented in Table 2. The consequences show that the rosin is unaffected by acid, seawater, and H2O. However, the movie exhibited hapless opposition to alkali which could be due to the presence of base hydrolysable ester groups in the movie. The alkyd movie dried fast on exposure, this was revealed by the touch, surface and dry through times which was found to be 6mins, 45mins and 2.28h severally as presented in Table 3, the drying ability of rosins is critical to their application as binder in surface coating.
The chemical opposition of the intercrossed binder in different chemicals is shown in Table 4. The consequences show that the binders are unaffected by seawater and H2O, but somewhat affected by the acid. However, they are affected to changing grades by base except sample A1, incorporating high sum of polyvinyl intoxicant, most immune. The hapless opposition of the binders to alkali may be explained on the footing that they are basically consisted of hydroxyl functional groups, Aigbodion et Al 2003. Table 4 shows that the VOC emanation decreases with the sum of polyvinyl ethanoate used. Sample A5 has the least emanation, demoing the effectivity of intercrossed movie formers in cut downing VOC emanation. Consequences corroborate with typical belongingss of solvent-based intercrossed binders such as good movie formation, high rubric and H2O and chemical opposition. The emulsion stableness from Table 4, show that the intercrossed binder exhibits colloidal stableness and better handling technique, Wicks et Al, 1992.
The consequences of this survey have shown that the oil extracted from Hura Crepitans seed can modify alkyd rosin, doing it suited as binder for surface coating applications. The alkyd movie showed good chemical opposition to acid, seawater and H2O, but non to alkali. An emulsion low VOC breathing intercrossed binder, consisting the oil-modified alkyd and poly vinyl ethanoate can be appropriately prepared utilizing additive alkyd benzine sulphonate as an emulsifier.