共查询到20条相似文献,搜索用时 0 毫秒
1.
聚乳酸纤维的染色性能 总被引:7,自引:0,他引:7
用9只不同结构的分散染料对聚乳酸纤维(PLA)进行染色,结果发现,对结晶度50%的PLA,有两只染料的上色率超过60%;对结晶度21%的PLA,有4只染料的上色率超过60%。用12只偶氮染料和13只蒽醌染料染成1/1标准浓度的PLA织物,其光褪色机理和影响因素与聚酯纤维和醋酸纤维相同,但褪色速度较快,耐晒牢度要差1—2级;PLA纤维染色应选用高浓度、高耐晒牢度的中温型分散染料。碱性溶液会引起PLA织物水解,60℃以上水解速度加快。 相似文献
2.
Yinzhong Guo Jon H. Hardesty Vijay M. Mannari John L. MassingillJr 《Journal of the American Oil Chemists' Society》2007,84(10):929-935
Ring-opening hydrolysis of epoxidized soybean oil in the presence of phosphoric acid was studied under varying experimental
conditions. The influence of type and amount of solvents, phosphoric acid content and water content on the rate of ring-opening
reactions and the characteristics of the derived products were studied. The soy-polyols prepared were characterized by determination
of hydroxyl content, viscosity measurements, determination of average molecular weight and polydispersity index (GPC). The
structural confirmation was done by FT-IR and 1H-NMR spectroscopy. The study shows that under the reaction conditions employed, a substantial degree of oligomerization due
to oxirane-oxirane, and/or oxirane-hydroxyl reaction takes place. It is possible to synthesize soy-polyols having varying
hydroxyl content and phosphate-ester functionality by controlling the type and amount of polar solvent and phosphoric acid
content. 相似文献
3.
聚乳酸(PLA)合成与改性的研究进展 总被引:1,自引:0,他引:1
在无数种类的可降解聚合物中,聚乳酸(PLA)塑料是一种脂肪族聚酯,是具有生物相容性的热塑性塑料,它是目前最具有发展前景的环境友好型塑料材料。这篇综述提供了目前的PLA市场信息,并介绍了近年来PLA合成和PLA改性方面的研究进展。 相似文献
4.
5.
Carbonated soybean oil was synthesized from epoxidized soybean oil and CO2 at atmospheric pressure and with tetrabutylammonium bromide (TBABr) as catalyst. Kinetic parameters, i.e., rate constants, activation energy and pre-exponential factors were determined. The effects of catalyst concentration and water content were studied. The reaction followed first-order kinetics with respect to epoxide at 100–140 °C. A steep increase in conversion (ca. 30 %) was obtained by increasing the amount of catalyst from 3 to 5 %. Further increasing the amount of catalyst to 7 % increased the conversion less than 10 %. The reaction proceeded faster when water was added; reaction times with water were ca. 70 % of the reaction times without water. Titration, FTIR and 1H-NMR analyses indicated ca. 90 % conversion and ca. 88 % selectivity towards the carbonate after 70 h at 120 °C with 5 % mol TBABr and 1:3 molar ratio of water to epoxide. 相似文献
6.
超临界工艺制备聚乳酸泡沫技术研究 总被引:2,自引:0,他引:2
超临界流体(SCF)是一种制备可降解聚合物泡沫的先进技术。利用超临界二氧化碳发泡成形技术,制备可降解高分子聚乳酸(PLA)泡沫材料,并通过条件试验确定了最适合的成形工艺参数,同时结合聚乳酸材料的物理性质,对控制泡沫形态的机理进行了研究。 相似文献
7.
Ring Opening of Epoxidized Soybean Oil with Compounds Containing Two Different Functional Groups 下载免费PDF全文
Kemal Karadeniz Hatice Akı Mustafa Yasin Sen Yakup Çalıkoğlu 《Journal of the American Oil Chemists' Society》2015,92(5):725-731
Epoxidized vegetable oils are desirable chemicals due to their eco‐friendly characteristics and their being a major source of many green products. Ring opening is one of the ways to convert these epoxidized oils to some new intermediates. The use of mono‐functional amines, alcohols, acid anhydrides and thioethers for epoxy ring opening has been reported in the literature. In this study, thioglycolic acid (TGA) bearing thiol and carboxylic acid as two different functional groups and methyl ester of thioglycolic acid (TGAME) were used. Currently, there is no reported literature describing epoxy ring opening using chemicals bearing two different functional groups simultaneously. In this way, two new polyols were synthesized, one with TGA (polyol 1) and one with TGAME (polyol 2). FTIR and 1H‐ and 13C‐NMR spectroscopy confirmed that the ring was opened by the carboxylic acid group of TGA, and the thiol group was not involved in the ring opening whereas the ring was opened by the thiol group in the case of TGAME. 相似文献
8.
Bo Lin Liting Yang Honghai Dai Aihua Yi 《Journal of the American Oil Chemists' Society》2008,85(2):113-117
The kinetics of the oxirane cleavage of epoxidized soybean oil (ESO) by methanol (Me) without a catalyst was studied at 50,
60, 65, 70 °C. The rate of oxirane ring opening is given by k[Ep][Me]2, where [Ep] and [Me] are the concentrations of oxiranes in ESO and methanol, respectively and k is a rate constant. From the temperature dependence of the kinetics thermodynamic parameters such as enthalpy (ΔH), entropy (ΔS), free energy of activation (ΔF) and activation energy (ΔE
a) were found to be 76.08 (±1.06) kJ mol−1, −118.42 (±3.12) J mol−1 k−1, 111.39 (±2.86) kJ mol−1, and 78.56 (±1.63) kJ mol−1, respectively. The methoxylated polyols formed from the oxirane cleavage reaction , were liquid at room temperature and had
three low temperature melting peaks. The results of chemical analysis via titration for residual oxiranes in the reaction
system showed good agreement with IR spectroscopy especially the disappearance of epoxy groups at 825, 843 cm−1 and the emergence of hydroxy groups at the OH characteristic absorption peak from 3,100 to 3,800 cm−1. 相似文献
9.
大豆油与过氧甲酸的环氧化动力学研究 总被引:1,自引:0,他引:1
通过大豆油中的双键与过氧酸发生环氧化反应,合成了环氧大豆油(ESO)。从动力学的角度,对反应过程中的各种影响因素,进行了较详细的研究。得知大豆油与过氧甲酸反应,大豆油的反应级数为1级,过氧甲酸的反应级数为2级,其反应活化能为22.77 kJ/mol。生成的环氧大豆油与体系内的甲酸发生水解开环反应,环氧大豆油的反应级数为0.5级,甲酸的反应级数为1级,该反应活化能为4.91 kJ/mol。通过所得动力学参数设定了无催化剂的环氧大豆油合成工艺,得到了环氧值高达6.85的环氧大豆油。 相似文献
10.
Optimization of Soybean Oil Based Pressure-Sensitive Adhesives Using a Full Factorial Design 下载免费PDF全文
Plant oils are attractive renewable feedstocks for biobased pressure‐sensitive adhesives (PSAs). In this study, we investigated how the PSA adhesion properties were influenced by the compositions comprised of epoxidized soybean oil (ESO), 3,4‐epoxycyclohexylmethyl 3,4‐epoxycyclohexanecarboxylate (ECHM), dihydroxyl soybean oil (DSO), rosin ester, and cationic photo initiator. When the amounts of ESO and photo‐initiator were constant, the variables of ECHM, DSO, and rosin amounts and their interactions were significant in influencing PSA peel adhesion strength, with p values smaller than 0.05 under a 95% significance level. Rosin amounts with the largest coefficient of 0.94 compared to the other variables are the most determinant factors. The peel adhesion strength was higher when using relatively a lower level of ECHM and a higher level of ESO and rosin. A model with the coefficient of determination (R2) of 95.06% was obtained to describe the relationship between the amount of resin constituents (ECHM, DSO, and rosin) and PSA peel adhesion strength in the experimental variable ranges. The optimal PSA formulation without cohesive failure was (ECHM = 0.04, DSO = 0.7, rosin = 0.7), resulting in a peel adhesion strength of 4.45 N/in. Structure–property relationships of the PSAs were established via thermal and rheological studies. 相似文献
11.
Mid-Oleic/Ultra Low Linolenic Acid Soybean Oil: A Healthful New Alternative to Hydrogenated Oil for Frying 总被引:1,自引:0,他引:1
To determine the frying stability of mid-oleic/ultra low linolenic acid soybean oil (MO/ULLSBO) and the storage stability
of food fried in it, tortilla chips were fried in MO/ULLSBO, soybean oil (SBO), hydrogenated SBO (HSBO) and ultra low linolenic
SBO (ULLSBO). Intermittent batch frying tests were conducted up to 55 h of frying, and then tortilla chips were aged up to
4 months at 25 °C. Frying oils were analyzed for total polar compounds to determine the frying stability of the oil. Tortilla
chips were analyzed for hexanal as an indicator of oxidative deterioration and by sensory analysis using a trained, experienced
analytical panel. Results showed no significant differences between the total polar compound levels for MO/ULLSBO and HSBO
after 55 h of frying, indicating a similar fry life. However, total polar compound levels for ULLSBO and SBO were significantly
higher than for either MO/ULLSBO or HSBO, indicating a lower oil fry life. Hexanal levels in aged tortilla chips fried in
SBO were significantly higher than in chips fried in any of the other oils. Tortilla chips fried in MO/ULLSBO and HSBO had
significantly lower hexanal levels than in chips fried in ULLSBO. A sensory analysis of rancid flavor intensity showed similar
trends to those for hexanal formation. The chips fried in SBO had the highest rancid flavor intensity, with significantly
lower hexanal levels in chips fried in HSBO and MO/ULLSBO. Based on these results, MO/ULLSBO not only had a good fry life
but also produced oxidatively stable fried food, and therefore would be a healthful alternative to HSBO.
Names are necessary to report factually on available data; however, the USDA neither guarantees nor warrants the standard
of the product, and the use of the name by the USDA implies no approval of the product to the exclusion of others that may
also be suitable. 相似文献
12.
13.
Bio-based epoxy materials were prepared from epoxidized soybean oil (ESO) with an anhydride-curing agent. Variation of anhydride/epoxy ratio (R) was found to have significant effect on the resulting properties of the materials. The properties were studied and compared by dynamic mechanical analysis (DMA), izod impact, scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The glass transition temperature reaches the maximum at stoichiometric ratio related to the cross-link density of the formed networks. These materials are thermally stable but exhibit a rapid decrease as the anhydride/epoxy ratio was increased. 相似文献
14.
Di-hydroxylated soybean oil (DSO) polyols with three different hydroxyl values (OHV) of 160, 240, and 285 mg KOH/g were synthesized from epoxidized soybean oils (ESO) by oxirane cleavage with water catalyzed by perchloric acid. The DSO were clear, viscous liquids at room temperature. The structure and physical properties of DSO were characterized using titration methods, Fourier-transform infrared spectroscopy (FTIR), gel permeation chromatography, rheometer, differential scanning calorimetry, and thermogravimetric analysis. The number average molecular weight of DSO160, DSO240, and DSO285 were 1,412, 1,781, and 1,899 g/mol, respectively, indicating that oligomerization occurred during DSO synthesis, which was further confirmed by FTIR. All DSO polyols exhibited non-Newtonian, shear thinning behavior. DSO with higher OHV were more viscous than those with lower OHV. All DSO were thermally stable up to 380 °C. These three DSO were formulated into pressure-sensitive adhesives (PSA) by copolymerizing with ESO using UV curing. The peel adhesion strength of the PSA was significantly affected by the OHV of DSO and DSO content. Maximal PSA adhesion strength of 4.6 N/inch was obtained with DSO285 and a DSO/ESO weight ratio of 0.75. 相似文献
15.
Partially hydrogenated oils (PHO) have been removed from the food supply due to adverse effects on risk for coronary heart disease (CHD). High-oleic soybean oils (HOSBO) are alternatives that provide functionality for different food applications. The objective of this study was to determine how consumption of diets containing HOSBO compared to other alternative oils, with similar functional properties, modifies LDL cholesterol (LDLc) and other risk factors and biomarkers of CHD. A triple-blind, crossover, randomized controlled trial was conducted in humans (n = 60) with four highly-controlled diets containing (1) HOSBO, (2) 80:20 blend of HOSBO and fully hydrogenated soybean oil (HOSBO+FHSBO), (3) soybean oil (SBO), and (4) 50:50 blend of palm oil and palm kernel oil (PO + PKO). Before and after 29 days of feeding, lipids/lipoproteins, blood pressure, body composition, and markers of inflammation, oxidation, and hemostasis were measured. LDLc, apolipoprotein B (apoB), NonHDL-cholesterol (HDLc), ratios of total cholesterol (TC)-to-HDLc and LDLc-to-HDL cholesterol, and LDL particle number and small LDL particles concentration were lower after HOSBO and HOSBO+FHSBO compared to PO (specific comparisons p < 0.05). Other than TC:HDL, there were no differences in lipid/lipoprotein markers when comparing HOSBO+FHSBO with HOSBO. LDLc and apoB were higher after HOSBO compared to SBO (p < 0.05). PO + PKO increased HDLc (p < 0.001) and apolipoprotein AI (p < 0.03) compared to HOSBO and HOSBO+FHSBO. With the exception of lipid hydroperoxides, dietary treatments did not affect other CHD markers. HOSBO, and blends thereof, is a PHO replacement that results in more favorable lipid/lipoprotein profiles compared to PO + PKO (an alternative fat with similar functional properties). 相似文献
16.
17.
绿色合成纤维--聚乳酸纤维 总被引:7,自引:0,他引:7
面对席卷全球的绿色浪潮,一种绿色的合成纤维——聚乳酸纤维,在纤维行业中越来越多被人们所重视。本文在介绍聚乳酸纤维的结构的基础上,详细地总结了聚乳酸纤维的包括物理性能、降解性能和安全性能在内的各种性能,具体地讨论了聚乳酸纤维的合成和纺丝过程,指出聚乳酸纤维具有广阔的应用前景和深远的生态意义,但当前的关键问题是降低合成聚乳酸树脂的成本。 相似文献
18.
Structure,Protein Interactions and In Vitro Protease Accessibility of Extruded and Pressurized Full-Fat Soybean Flakes 总被引:3,自引:1,他引:2
Stephanie Jung Abdullah Mahfuz Devin Maurer 《Journal of the American Oil Chemists' Society》2009,86(5):475-483
The objectives of the present study were to determine how extrusion (barrel temperature of 100 °C) and high-pressure processing
(HPP, 200 and 500 MPa, 15 min, 25 °C) of full-fat soybean flakes (FFSF) modified the structure of soybean cotyledon cells,
the protein interactions and the in vitro protease accessibility. Cellular disruption of the cotyledon cells was only observed
for extruded FFSF. Extrusion and HPP at 500 MPa favored formation of insoluble protein aggregates, in which oil was entrapped.
High pressure size exclusion chromatography (HPSEC) and extraction methods using buffers containing SDS and 2-mercaptoethanol
suggested that noncovalent interactions were the main forces in protein aggregate formation during HPP 500 MPa and extrusion.
Intermolecular cross-linking by disulfide bonding was also involved in insoluble aggregates, but at a lesser extent than noncovalent
interactions. Extrusion and HPP 500-MPa treatment enhanced the proteolytic attack, while treatment at 200 MPa had no impact.
Drastic changes in the peptide profile of the extracted proteins were, however, only observed for the enzyme-treated 500-MPa
FFSF. Optimal oil and protein extraction yields required cellular disruption of cotyledon cells and hydrolysis of protein
aggregates, which were obtained with enzyme-assisted aqueous extraction of extruded FFSF. 相似文献
19.
The Interaction of the Soybean Seed High Oleic Acid Oil Trait With Other Fatty Acid Modifications 下载免费PDF全文
Kristin Bilyeu Mária Škrabišová Doug Allen Istvan Rajcan Debra E. Palmquist Anne Gillen Rouf Mian Hyun Jo 《Journal of the American Oil Chemists' Society》2018,95(1):39-49
Oil value is determined by the functional qualities imparted from the fatty acid profile. Soybean oil historically had excellent use in foods and industry; the need to increase the stability of the oil without negative health consequences has led to a decline in soybean oil use. One solution to make the oil stable is to have high oleic acid (>70%) and lower linolenic acid content in the oil. Other fatty acid profile changes are intended to target market needs: low‐saturated fatty acid and high stearic acid content in the oil. The objective of this study is to determine the interaction of the high oleic acid oil trait with other alleles controlling fatty acid profiles. Soybean lines containing high oleic acid allele combinations plus other fatty acid modifying alleles were produced, and the seed was produced in multiple field environments over 2 years. Stable high oleic acid with low linolenic acid (<3.0%) was achieved with a 4‐allele combination. The target of >20% stearic acid in the seed oil was not achieved. Reducing total saturated fatty acids below 7% in a high oleic acid background was possible with mutant alleles of both an acyl‐ACP thioesterase B and a β‐ketoacyl‐[acyl‐carrier‐protein] synthase III gene. The results identified allele combinations that met the target fatty acid profile thresholds and were most stable across environments. 相似文献
20.
研究了利用废豆油和甲醇作为原料,在催化剂甲醇钠的作用下通过酯交换反应,制备脂肪酸甲酯即生物柴油和丙三醇(甘油),根据正交实验结果,较佳的工艺条件为:摩尔比7∶1、反应温度60℃、反应时间90min、催化剂用量0.8%。在此工艺条件下,生物柴油的收率可达93.71%;精馏后的甘油纯度较高,达到97.5%以上。 相似文献