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Sa-Ad Riyajan Isara IntharitPramuan Tangboriboonrat 《Industrial Crops and Products》2012,36(1):376-382
The polymer composite was prepared from the wastes of natural rubber glove (NRG) and polystyrene foam (PSF) blended with cellulose from sugar cane leaves via the laminate method. The NRG and PSF were firstly dispersed in toluene under continuous stirring. Then, maleic anhydride (MA) was added into the mixture. Effects of blend ratio and of MA content (0.5-15%, w/w) on physical properties of the polymer composite were investigated. The toluene resistance of the polymer blend was improved after adding MA and cellulose. The highest toluene resistance was achieved when using 12% cellulose. The chemical reactions of MA with polymer blend and with composite were confirmed by ATR-FTIR. The hardness of the polymer blend and composite increased as a function of PSF. In addition, their impact strength increased with increasing NRG and cellulose contents. 相似文献
3.
Meadowfoam oil methyl ester was metathetically cleaved with ethylene catalyzed by Re2O7–B2O3/Al2O3–SiO2 + SnBu4 or bis(tricyclohexyl phosphine) benzylidene ruthenium dichloride yielding -olefins, ,ω-dienes and 5-hexenoic acid methyl ester as the main product. The corresponding ω-epoxy fatty acid ester was achieved by chemoenzymatic epoxidation with H2O2 in the presents of Novozym® 435. Glutaric acid mono methyl ester was synthesized by ruthenium-catalyzed oxidative cleavage with peracetic acid. Hydrocarboxylation with carbon monoxide/methanol yielded pimelic acid dimethyl ester. Metathetical dimerization of 5-hexenoic acid methyl ester yielded 5-decen-dioic acid dimethyl ester, which was subsequently polycondensed with ethylene glycole and 1,4-butanediol to high molecular weight polyesters. The ω-unsaturated ester was directly copolymerized with ethylene by an insertion-type palladium-catalyzed reaction to a high molecular weight functional polyolefin. The 5-epoxy hexanoic acid ester was polymerized to a comb like polyether. 相似文献
4.
Low molecular weight copolymers of maleic anhydride and vinyl acetate were prepared to develop formaldehyde free cross-linking
agents. Since lower molecular weight is favorable for efficient penetration of the finishing agent into the cotton fibers
in the padding process, the concentration of the initiator, chain transfer agent and the monomer ratios were varied to obtain
copolymers of low molecular weights. The prepared polymers were characterized by GPC,1H-NMR, FTIR, DSC and TGA. Copolymers of molecular weights of 2 000 to 10 000 were obtained and it was found that the most
efficient method of controlling the molecular weight was by varying the monomer ratios. Poly(maleic anhydride-co-vinyl acetate)
did not dissolve in water, but the maleic anhydride residue hydrolyzed within a few minutes to form poly(maleic acid-co-vinyl
acetate) and dissolved in water. However, the maleic acid units undergo dehydration to form anhydride groups on heating above
160 °C to some extent even in the absence of catalysts. The possibility of using the copolymers as durable press finishing
agent for cotton fabric was investigated. Lower molecular weight poly(maleic anhydride-co-vinyl acetate) copolymers were more
efficient in introducing crease resistance, which appears to be due to the more efficient penetration of the crosslinking
agent into cotton fabrics. The wrinkle recovery angles of cotton fabrics treated with poly(maleic anhydride-co-vinyl acetate)
copolymers were slightly lower than those treated with DMDHEU and were higher when higher curing temperatures or higher concentrations
of copolymer were used, and when catalyst, NaH2PO2, was added. The strength retention of the poly(maleic anhydride-co-vinyl acetate) treated cotton fabrics was excellent. 相似文献
5.
Hongwei Pan Dandan Ju Yan Zhao Zhe Wang Huili Yang Huiliang Zhang Lisong Dong 《Fibers and Polymers》2016,17(10):1540-1549
Poly(butylene adipate-co-terephthalate) (PBAT) and thermoplastic starch (TPS) were blended by using maleic anhydride (MA) as a compatibilizer. Preferentially, TPS could be reacted with MA to obtain maleated thermoplastic starch (MTPS). Then PBAT/MTPS blends were blown films using blown technique. From dynamic mechanical analysis, the shifting of the glass transition temperatures toward each other suggested that PBAT was partially miscible with MTPS. From wide angle X-ray diffraction analysis, the degree of crystallinity of PBAT/MTPS films was decreased with increasing MTPS content. From rheological measurements, the melt elasticity and viscosity of the PBAT/MTPS blends increased. It was benefit to extrude blend and blow film. The contact angle values of bipolar liquid water were range from 100.2 to 77.7 ° decreased with increasing MTPS content from 0 to 50 %. The PBAT/MTPS films could satisfy the requirement for applying in our life. 相似文献
6.
Green composites from Pattawia pineapple leaf fiber (PALF) and poly(lactic acid) (PLA) were prepared. The mechanical method was chosen to extract PALF from fresh leaves due to this method gave high yield of fiber, short extraction time, and environmental friendly. Tensile and thermal properties, together with morphology of the fibers were disclosed. The fibers were conducted into a specified length of 1–3 mm and blended with PLA, using a twin screw extruder, with the PALF content of 10–50 wt%. Tensile testing, morphology investigation and thermogravimetric analysis were applied. Preliminary results showed that tensile modulus of the composites depended on PALF content. The tensile modulus and elongation at break of the composite containing 40 % PALF was about 48 %, and 111 % increase, respectively, compared with that of PLA. With addition of maleic anhydride coupling agent, such the composite showed the tensile modulus of 5.1 GPa, which was 34 % higher than that of the non-coupling agent composite, and about 104 % higher than that of PLA. Although the elongation at break of the composite containing 40 % PALF was found to dramatically increase by 111 %, the introduction of maleic anhydride in such the composite caused only 57 % increase in the elongation at break compared with that of PLA. Finally, a pilot product of square boxes was produced successfully from the proposed composite, by conventional injection molding process. 相似文献
7.
以大豆油为原料,KOH作催化剂,通过大豆油与乙醇的酯交换反应合成了大豆油脂肪酸乙酯。应用响应曲面分析法中的Box-behnken模型对影响大豆油脂肪酸乙酯转化率的四个主要因素(催化剂用量、醇油摩尔比、反应温度、反应时间)进行了优化。研究表明大豆油脂肪酸乙酯的最佳合成工艺条件为:KOH用量1.3%,醇油比8.3∶1,反应温度74.8℃,反应时间130min。在此条件下,酯转化率达98.93%。 相似文献
8.
生物柴油物理特性参数的估算与误差分析 总被引：1，自引：0，他引：1
以生物柴油脂肪酸酯含量为基础,应用Matlab编制了包含15种脂肪酸酯的生物柴油物性参数预测程序,并应用所编程序估算了大豆油甲酯生物柴油的密度、表面活力、黏度和导热系数;分析比较了各种估算方法的精度.结果表明:在生物柴油密度估算中,修改Raekett方程的估算精度较高;Sastfi-Rao方法估算生物柴油低温黏度所得结果与实测值最接近,其估算精度较高;Miller方法和Macleod-Sugden关联式估算生物柴油表面张力的精度较其它几种方法高;建议在生物柴油导热系数估算中应用Sastri方法. 相似文献
9.
Maleic acid (MA) and itaconic acid (IA) used as crosslinking agents for cotton fabrics are more cost-effective than the most efficient nonformaldehyde crosslinker 1,2,3,4-butanetetracarboxylic acid (BTCA), but poor stability of finishing bath and fabric yellowing are the main disadvantage of MA/IA in situ polymerization and crosslinking system. In this research, the application performance improvement of MA/IA crosslinking system for cotton fabrics was studied. Replacement of the widely used sodium hypophosphite (SHP) with potassium hypophosphite (PHP) as catalyst allowed for obtaining a stable finishing bath under ambient temperature and led to improved final durable press (DP) performance of the treated fabrics. The influences of PHP concentration, curing temperature, and curing time on the performance of finished fabrics were investigated. Cotton fabrics treated by MA/IA/PHP crosslinking system exhibited comparable DP performance and laundering durability to that finished with BTCA. To address the fabric yellowing problem, the residual MA and IA attached on the treated fabrics by single-ended ester linkage was determined by HPLC. The data indicated that the degree of fabric yellowing was linearly related to the unpolymerized carboxylic acid MA and IA concentration on the treated fabrics. Several approaches were explored to improve the whiteness of MA/IA/PHP crosslinked fabrics. It was found that steam drying with 30-50 % humidity could effectively improve fabric whiteness. The findings of this study have significant implications for better application of unsaturated polycarboxylic acids in crosslinking of cellulose. 相似文献
10.
Aiello A Fattorusso E Imperatore C Irace C Luciano P Menna M Santamaria R Vitalone R 《Marine drugs》2011,9(6):1157-1165
Chemical analysis of the Mediterranean ascidian Polyandrocarpa zorritensis (Van Name 1931) resulted in the isolation of a series of molecules including two monoindole alkaloids, 3-indolylglyoxylic acid (3) and its methyl ester (4), 4-hydroxy-3-methoxyphenylglyoxylic acid methyl ester (1) and a new alkaloid we named zorrimidazolone (2). The structure of the novel compound 2 has been elucidated by spectroscopic analysis and bioactivity of all compounds has been investigated. Zorrimidazolone (2) showed a modest cytotoxic activity against C6 rat glioma cell line. 相似文献
11.
Do Un Park Nam Koo Han Ji Hyeong Ryu Won Ho Park Young Gyu Jeong 《Fibers and Polymers》2018,19(10):2007-2015
We have synthesized a series of copolymers with different compositions of acrylonitrile (AN, 80–100 wt%), methyl acrylate (MA, 4–20 wt%) and itaconic acid (IA, 0–3 wt%) by using an efficient aqueous suspension polymerization, and have investigated the molecular structure and thermal stabilization behavior of PAN homopolymer, AN/MA-based bipolymers, and AN/MA/IA-based terpolymers by adopting 1H/13C-NMR and thermal FT-IR analyses. The viscosity-average molecular weight of the synthesized polymers were measured to be ~263,000 g/mol. The reactivity ratios of AN and MA for all the copolymers were evaluated to be 0.99 and 1.05, respectively. Accordingly, the output compositions of the synthesized copolymers were quite consistent with the input monomer compositions. The 13C NMR analysis revealed that all the synthesized polymers have an atactic chain configuration, regardless of the feed composition. The structural evolutions during the thermal stabilization process of the copolymers in air environment were characterized by monitoring the temperature-dependent changes of characteristic absorbance bands at 2240 cm-1 (C≡N), 1595 cm-1 (C=N) and 1660 cm-1 (C=O) with aid of thermal FT-IR spectroscopy. It was found that the IA unit in the terpolymers accelerated the oxidation and cyclization reactions, unlike the retarding effect of MA unit, and that the onset temperatures of the oxidation reaction of the copolymers with IA unit was lower than that of the cyclization reaction. 相似文献
12.
Haydar U. Zaman Mubarak A. Khan Ruhul A. Khan Sushanta Ghoshal 《Fibers and Polymers》2012,13(5):593-599
Coir fibers were modified with methyl acrylate (MA) mixed with methanol (MeOH) under thermal curing method at different temperatures (40?C80 °C) for different curing times (20?C60 min). A series of solutions of different concentrations of MA in methanol along with 2 % benzoyl peroxide, were prepared. Monomer concentration, curing temperature, and curing time were optimized with the extent of grafting of monomer and mechanical properties of cured fiber and found to be 30 % MA, 60 °C and 40 min curing time registered as better performance (Grafting (Gr) = 5.7 %, tensile strength (TS) = 72 %, elongation at break (Eb) = 88 %) than those of untreated fiber. For further improvement of the properties, untreated coir fibers were pretreated with gamma and UV radiations at different doses and then pretreated fibers were soaked in the optimized monomer and cured under optimum conditions. Coir fiber pretreated with UV radiation and grafted with optimized monomer showed the best properties such as Gr (7.12 %), TS (132 %), and Eb (153 %) over raw fiber. Water uptake and simulated weathering test of untreated and treated coir fibers were studied. 相似文献
13.
A.A. Abdelmalik A.P. AbbottJ.C. Fothergill S. DoddR.C. Harris 《Industrial Crops and Products》2011,33(2):532-536
This report presents a method for synthesizing base-stock for green industrial product from a vegetable oil with a high composition of unsaturated fatty acids. Epoxy methyl ester of palm kernel oil was synthesized from laboratory purified palm kernel oil using a two-step reaction and the products were used as a base-stock for green electrical insulation fluid. Epoxidized palm kernel oil was first prepared through epoxidation reaction involving purified palm kernel oil, acetic acid and hydrogen peroxide in the presence of amberlite as catalyst which lasted for 4 h. It was then followed by transesterification reaction involving the epoxidized product and methanol in the presence of sodium hydroxide as catalyst to synthesize the corresponding epoxy methyl ester. The thermal and electrical breakdown properties of the epoxy methyl ester demonstrated significantly improved properties for its use as raw material for bio-based industrial products such as electrical insulation fluids. 相似文献
14.
为全面了解海南传统黎药艾纳香抗菌药效物质基础,本研究采用硅胶柱色谱、凝胶色谱以及高效液相色谱技术对艾纳香提取物进行系统化学成分研究。结果显示:共分离鉴定6个绿原酸类成分:3,5-O-二咖啡酰奎尼酸乙酯(1),3,5-O-二咖啡酰奎尼酸甲酯(2),3,4-O-二咖啡酰奎尼酸甲酯(3),3,4-O-二咖啡酰奎尼酸(4),3,5-O-二咖啡酰奎尼酸(5),1,3,5-O-三咖啡酰奎尼酸(6)。化合物1~6均为首次从该植物中分离得到,其中化合物1为新天然产物。抗细菌活性评价显示化合物3对枯草芽孢杆菌及化合物6对金黄色葡萄球菌均具有较强抑制活性,MIC值均为64μg/mL,推测绿原酸类为艾纳香的重要抗菌活性组成。 相似文献
15.
“安粳698”高产栽培数学模型研究 总被引：1，自引：0，他引：1
为进一步探索"安粳698"的优化高产配套栽培技术,采用二次回归通用旋转组合设计,研究"安粳698"产量与栽插密度、N、P、K施用量间的关系,建立各因素与产量指标的数学模型:Y=548.21-12.83X1-20.21X2+4.29X3+8.75X4+3.80X12-13.64X22-6.32X32-0.20X42-0.56X1X2+3.50X1X3+1.94X1X4+2.13X2X3-4.19X2X4-0.88X3X4,提出了"安粳698"获得535.55kg/667 m2产量以上的优化方案,即栽插密度为1.823 4万～1.880 2万穴/667 m2,N施用量5.845～6.930 kg/667 m2,P2O5施用量8.239 5～9.760 5 kg/667 m2,K2O施用量11.605～13.21 kg/667 m2。各因素对安粳698产量的影响大小为施氮量>栽插密度>施钾量>施磷量。 相似文献
16.
Arun Ghosh Richard S. Carran Anita J. Grosvenor Santanu Deb-Choudhury Stephen R. Haines Jolon M. Dyer 《Fibers and Polymers》2016,17(1):9-14
The poultry meat processing industry produces large amounts of feather meal, which is traditionally used as lowvalue plant fertilizer or fish nutrient. A higher value application for feather meal is described in this paper - a thermal blending and compression molding method to create compostable composites out of environmentally friendly materials: feather meal, glycerol, and a biodegradable copolymer of methyl vinyl ether and maleic anhydride (MVEMA). The composite’s mechanical, microstructural and chemical characteristics are described. Feather meal plasticized only with glycerol is mechanically fragile, with average tensile strength of 1.7 MPa, Young’s modulus of 296 MPa and strain-at-failure of 0.6 %. With the addition of MVEMA copolymer, feather meal is transformed into a ductile plastic composite, with tensile modulus reduced 2- to 5-fold and strain-at-failure increased 4- to 25-fold. These properties are ideal for creating feather mealbased compostable bioplastics for agricultural and industrial applications. 相似文献
17.
N. Vedaraman Sukumar PuhanG. Nagarajan B.V. RamabrahmamK.C. Velappan 《Industrial Crops and Products》2012,36(1):282-288
Many research reported vegetable oil as a potential substitute for diesel engines with its ester form known as biodiesel. The biodiesel can be prepared by different process using vegetable oil and alcohol. The common process used for biodiesel preparation is known as transesterification. This paper presents the transesterification of Sal oil (Shorea robusta) into Sal oil methyl ester (SOME) and its performance in direct injection diesel engine. Several process parameters such as catalyst quantity, molar ratio of alcohol, reaction temperature and reaction time were studied and the optimized process conditions are amount of catalyst (NaOH) - 0.25 wt%, alcohol (methanol) - 150% excess, reaction temperature - 65 °C and reaction time - 1.5 h. The studies with SOME as fuel in the direct injection diesel engine shows that the exhaust emissions such as CO, HC and NOx are reduced by 25%, 45% and 12%, respectively compared to diesel without significant difference in thermal efficiency. Based on this study it is concluded that the SOME can be used as fuel without any modifications in the engine and hence this biodiesel can be a potential substitute to standard diesel fuel. 相似文献
18.
《Industrial Crops and Products》2005,21(1):25-31
The oilseed crop Camelina sativa (camelina) has lower production costs than oilseed rape in some climates. For this reason, the production of biodiesel-grade methyl ester from camelina oil was evaluated. The evaluation included quality assessment of esters produced in laboratory and pilot plant, an examination of methods of improving ester low-temperature properties, and vehicle trials. Laboratory esterifications gave ester yields similar to rape-seed oil. Six 350 kg batches of unrefined camelina oil with acid values from 3 to 6 were esterified in a pilot plant. Ester-specific properties were satisfactory with one exception; the iodine number of 155 far exceeded the value of 120 required by the relevant EU standard. Fuel-specific properties of the camelina methyl esters were largely within specification, though low-temperature behaviour could be a problem in some climates. This problem could be overcome by the use of suitable pour-point depressants or by blending with diesel oil. In vehicle tests, the reduction in fuel economy with camelina ester was similar to that with biodiesel from other feedstocks. The high iodine number of camelina methyl ester did not lead to a more rapid deterioration of the lubricating oil. However, it was concluded that further engine trials would be needed before the use of camelina ester as an undiluted vehicle fuel could be recommended. 相似文献
19.
岭头单枞乌龙茶香气及化学组成特征 总被引：12，自引：3，他引：12
岭头单枞是广东省的优良乌龙茶品种，其成茶具有一种特殊的蜜香。对其鲜叶和成茶分析结果表明，其醚浸出物较高，儿茶素含量较低。检出了７８种香气成分，秋茶的含量及种类比春茶丰富。成茶中含量较多的有：芳樟醇及其氧化物（秋茶１３．４１％，春茶９．４５％）、法呢烯（秋茶１０．７６％，春茶４．７１％）、橙花叔醇（秋茶８．５８％）、己酸，２－丙烯酯（秋茶１０．５６％）、十六碳酸（秋茶５．１２％、春茶１．５７％）、植醇（秋茶３．０４％，春茶８．６１％）、亚油酸甲酯（秋茶５．７％）、γ－亚麻酸甲酯（秋茶３．３５％）等，尤其是最后两种成分，在其他茶叶中少有检出。 相似文献
20.
N. SutivisedsakH.N. Cheng M.K. DowdG.W. Selling A. Biswas 《Industrial Crops and Products》2012,36(1):127-134
Polymeric composites based on cotton burr and cottonseed bull have been prepared by melt blending and extrusion. For poly(lactic acid) (PLA) and low-density polyethylene (LDPE), addition of the fillers slightly changed the composite's thermal properties but significantly decreased the composite's mechanical properties. Heat treatment prior to extrusion resulted in composites with better tensile strength and Young's modulus. The use of maleic anhydride and peroxide only slightly improved the physical properties of the LDPE materials, but the effect was less clear for the PLA materials. The PLA-filler composites may be useful for lowering the cost of the materials in applications that can tolerate the decreased properties. In addition, the addition of fillers to LDPE might be beneficial in applications to improve stiffness or to improve biodegradability. 相似文献