In this paper, lignin could partly replaced phenol to prepare lignin-phenolic(LPF) foam.The effects of amount of lignin on mechanical properties, thermal stability, fire-retardant and micro-structure of LPF foam. The results indicated that the addition of lignin decreased the brittleness and flexibility of foam, and the foam hole became larger in diameter and distributed more unevenly. When the lignin replacement amount was lower, the foam had regular foam hole structure and even distribution of foam hole, the size of foam hole increased with an increase of lignin content, SEM observations were in accordance with the early research of the mechanical properties of foams. And the addition of lignin slightly affected the fire-retardant and thermal stability of foam. When lignin replacement amount was 30% and 40%, the critical oxygen index of foam was even slightly higher than the pure PF foam.
Novel dimer fatty acids-based vinyl ester resin monomer was prepared via simple ring-opening and esterification reaction with the aid of dimer fatty acids (DA) and glycidyl methacrylate (GMA) as raw material. The effects of different catalyst system, reacting time and reacting temperature on the yield, color, and viscosity of the final product were analyzed. The results of optimal experiments showed that BTEAC catalyst could make the final product with moderate viscosity and lighter color, the optimal BTEAC catalyst addition amount was 0.5wt.%, the optimal reacting temperature and reacting time was 115 °C and 2h, respectively. FTIR and 13C-NMR demonstrated that the target product had been successfully synthesized.
The phenolic(PF) foams were prepared used low-temperature foaming and curing method. The optimum low-temperature foaming processing technology conditions and material proportioning were described below. The curing temperature was 40 °C, the amount of foaming agent iso-pentane was 8-10wt.%, tween-80 dosage was 6-7wt.%, the amount of composite curing agent was 15-18wt.%.The effects of low-temperature foaming on mechanical properties, heat insulation, fire-retardant, foam hole form and micro-structure were discussed. 40°C and 70°C curing PF foam performance comparison results showed that low-temperature curing technology slightly affect the fire-retardant properties of PF foam. And excellent overall performance PF foam were prepared with 40°C foaming technology, the foam hole morphology structure, toughness and strength of PF foam were better. In addition, the low-temperature curing PF foam had more even foam hole distribution, more regular foam hole structure, more clean foam hole arrangement.
To study the fatty acid composition and analysis the variation among the samples of tung oil collected from Guangxi,Chongqing, Hunan, Hubei and Guizhou Provinces of China.Gas chromatography-mass spectrometry(GC-MS) were employed to determine the fatty acid composition of tung oil.The results show that the main composition of the tung oil in China are n-hexadecanoic acid, linoleic acid, oleic acid, stearic acid, α-octadecatrienoic acid, β-octadecatrienoic acid. Tung oil contains octadecatrienoic acid 72.56~88.59% and polyunsaturated fatty acids 80.26~92.39%. The content of octadecatrienoic acid and polyunsaturated fatty acids in tung oil are different between different regions and different varieties.
Carbohydrates are the main source which required to maintain energy equilibrium and normal life activities. In acorn kernel, soluble polysaccharides and starch are the main carbohydrate. In order to accurately measure the carbohydrate content of the acorn kernel in Nanjing Area. Dual-wavelength spectrophotometry and anthrone-sulfuric methods were applied to measure the content of amylose, amylopeetin and soluble polysaccharides,respectively.The other two samples were simultaneously measured for comparative analysis.Testing results show that acorn kernel contain about 79.40% of starch, amylopectin content was up to 59.01%, polysaccharide content is 6.53%.The results indicate that acorn kernel was an important raw material for preparing food, feed and starch-based composites.
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