无规支化苯乙烯-甲基丙烯酸甲酯共聚物合成及表征

以α-溴代异丁酸叔丁酯(tBBiB)为引发剂,CuBr/2,2'-联吡啶(BPy)为催化体系,二乙烯基苯(DVB)为支化单体,经原子转移自由基聚合(ATRP),在90℃下进行了苯乙烯(St)和甲基丙烯酸甲酯(MMA)的共聚合反应,研究了不同单体组成对反应的影响.用红外光谱(FT-IR)、核磁共振氢谱(1H-NMR)、凝胶渗透色谱(GPC)、多角激光散射仪(MALLS)分别对聚合反应过程和聚合物进行了表征和分析.结果表明:反应表现出活性聚合特征,Mw.MALLS＞3.9×105;Mw.MALLS/Mw.GPC＞1,说明反应生成了St与MMA的无规支化共聚物:当St与MMA摩尔比为3∶1时,共聚物中St单元的含量最大.     

泡沫级专用三(2-羟乙基)异氰尿酸酯改性蜜胺树脂

采用三(2-羟乙基)异氰尿酸酯(THEIC)改性蜜胺树脂,通过粘度和力学性能测试研究了改性树脂的聚合工艺条件(如物料配比、反应时间、改性剂添加量、固含量等)对体系聚合反应及改性产物韧性的影响,采用IR光谱对改性树脂的结构进行了表征。结果表明,THEIC参与了反应,植入蜜胺树脂的分子链中,加大了三嗪环之间的距离,起到增韧改性的目的。适合发泡用THEIC改性蜜胺树脂的适宜的工艺条件为:n(M)∶n(F)=1∶2.8,pH=9.0~9.5,反应温度(95±1)℃,时间80~100 min,固体质量分数为75%,THEIC添加量为10%。     

脂肪酶催化液-固反应合成聚丁二酸丁二酯

以固定化酶Novozyme435为催化剂,在液-固混合体系中经酶催化1,4-丁二醇与丁二酸缩聚合成聚丁二酸丁二酯(PBS),考察反应条件对聚合效果的影响。采用GPC法对产物重均分子量Mw和分子量分布MwMn进行了测定;采用核磁共振法对产物结构进行了鉴定。最佳反应条件为:丁二酸与1,4-丁二醇的物质的量的比为17:23,Novozyme435用量为底物总质量的7%,聚合温度为65℃。以底物总质量200%的二苯醚为反应介质,真空条件下聚合48h,PBS的最大Mw可达到50800(MwMn=1.36)。实验表明,丁二酸在反应介质中的溶解程度和副产物水的去除是限制PBS聚合效果的最主要因素。     

有机硅改性丙烯酸酯乳液的制备及表征

以γ-甲基丙烯酰氧丙基三甲氧基硅烷(KH-570)、八甲基环四硅氧烷(D4)、丙烯酸酯类单体为原料,制备了有机硅改性丙烯酸酯乳液.考察了乳化剂配比、有机硅用量对乳液及乳胶膜性能的影响,并用红外光谱、凝胶渗透色谱、透射电镜进行了表征.结果表明KH-570先与低聚体D4开环预聚,再与丙烯酸酯类单体进行自由基聚合,可得到有机硅改性丙烯酸酯乳液;当有机硅占单体总质量的9%,其中m(KH-570)∶m(D4)=1∶9,m(MS-1)∶m(AEO)=2∶1时,乳液的黏度、凝胶率和乳胶膜的硬度随有机硅用量的增加而增大,乳胶膜的吸水率则降低;乳胶粒表面光滑均一,呈规则的圆球状,平均粒径为100 nm,其重均摩尔质量Mw=1.75×104g/mol,摩尔质量分布Mw/Mn=1.3.     

泡沫级THEIC改性蜜胺树脂的研究

本文研究主要以三(2-羟乙基)异氰尿酸酯作为改性剂对蜜胺树脂进行改性.采用旋转粘度计测量反应体系动力粘度,根据动力粘度变化定性表征缩聚产物分子量和反应速率快慢,从而考察改性树脂的聚合工艺条件(如物料配比、反应时间、改性剂添加量、固含量等)对体系聚合反应的影响.并通过IR光谱、TG-DSC等测试手段对改性树脂的结构、热稳...     

可生物降解苯乙烯-马来酸酐共聚物的合成工艺研究

以苯乙烯与马来酸酐为聚合单体,在适宜的条件下合成得到可降解的苯乙烯-马来酸酐共聚物。考察了引发剂用量、反应温度、反应时间、物料比等因素对SMA共聚物中马来酸酐含量及特性粘数的影响。结果表明,BPO量为0.3%、n(St)/n(MA)=1.2∶1、聚合反应温度125℃、聚合反应时间3 h,可以得到相对分子质量Mn=27 303、分子量分布Mw/Mn=1.873 736的SMA共聚物。利用红外谱(IR)、凝胶渗透色谱(GPC)对产物进行了表征确认。     

可生物降解苯乙烯-马来酸酐共聚物的合成工艺研究

以苯乙烯与马来酸酐为聚合单体,在适宜的条件下合成得到可降解的苯乙烯-马来酸酐共聚物。考察了引发剂用量、反应温度、反应时间、物料比等因素对SMA共聚物中马来酸酐含量及特性粘数的影响。结果表明,BPO量为0.3%、n(St)/n(MA)=1.2∶1、聚合反应温度125℃、聚合反应时间3 h,可以得到相对分子质量Mn=27 303、分子量分布Mw/Mn=1.873 736的SMA共聚物。利用红外谱(IR)、凝胶渗透色谱(GPC)对产物进行了表征确认。     

泡沫级THEIC改性蜜胺树脂的研究

以三(2-羟乙基)异氰尿酸酯作为改性剂对蜜胺树脂进行改性,采用旋转黏度计测量反应体系动力黏度,根据动力黏度变化定性表征缩聚产物相对分子质量和反应速率快慢,考察了改性树脂的聚合工艺条件(如物料配比、反应时间、改性剂添加量、固含量等)对体系聚合反应的影响;并通过IR光谱、TG-DSC等对改性树脂的结构、热稳定性进行了表征....     

手性聚苯胺改性硅藻土复合材料的制备

在樟脑磺酸的手性诱导作用下,在硅藻土表面原位聚合苯胺得到手性聚苯胺改性硅藻土复合材料,利用红外吸收光谱(FTIR)和扫描电子显微镜(SEM)对复合材料的结构进行表征,表明苯胺在硅藻土表面进行了原位聚合,聚合产物呈现纳米棒状态。通过测试复合材料的循环伏安特性曲线(CV)表征材料的电化学性能,对比了在不同手性聚苯胺/硅藻土配比以及不同时间条件下改性材料的性能差异。结果表明:随着苯胺聚合量的增大以及反应时间的增加,复合材料的电化学性能会呈现先增大后减小的趋势。     

聚天冬氨酸的结构及其阻垢性能研究

对由马来酸酐胺化热聚合(方法Ⅰ)和由L-天冬氨酸单体热缩聚法(方法Ⅱ)合成的聚天冬氨酸(PASP)利用凝胶渗透色谱和红外光谱对产物进行了分析比较,认为工艺路线和反应条件的改变影响了产物的平均相对分子质量和相对分子质量的分布。产物的静态阻垢试验结果表明,方法Ⅰ所得产物在重均相对分子质量(Mw)为3000左右时的阻垢率和方法Ⅱ所得产物在Mw为5200左右时的阻垢率相当。利用SEM对碳酸钙垢型变化的研究结果表明．PASP的加入导致了成垢严重的晶格畸变。     

我国脂肪酸的生产和应用

简要介绍脂肪酸的分类、原料来源、生产工艺、品种以及用途。并对我国脂肪酸的生产现状进行了分析。重点介绍了脂肪酸在我国橡胶工业中、塑料助剂等领域的应用,脂肪酸甲酯作为表面活性剂在不同领域的广泛应用,最后还简述了癸二酸和改性醇酸树脂应用。     

酸液体系的研究现状分析和现场应用

酸化解堵与压裂改造相比,它具有施工相对简单和成本相对较低等特点,所以酸化解堵是一项各油田广泛使用的油气田增产技术。酸化解堵技术已有将近100历史,现已研制出具有不同特点的酸液体系,如乳化酸、泡沫酸、固体酸、多氢酸等,基本能满足复杂地质条件对酸液的要求。     

油酸的精制研究

油酸酰胺是一种很好的塑料添加剂 ,可用作塑料加工成型时的脱膜剂、润滑剂。油酸的原料来源很广 ,牛油、羊油、猪油等动物油油脂以及大豆油、花生油、棕榈油等植物油脂中都含有大量的油酸。由于油酸的来源和生产方法多种多样 ,因此其所含的脂肪酸种类及含量都不尽相同。除油酸外 ,还有亚油酸、亚麻酸等高不饱和脂肪酸。针对油酸中因含有大量的多不饱和组分如亚油酸、亚麻酸而容易产生氧化泛黄的问题 ,采取了尿素络合法对原料油酸进行精制 ,以减少原料中亚油酸、亚麻酸组分的含量。经气相色谱验证 ,产品达到了应用指标 ,提高了产品的抗氧性。     

磷钼杂多酸的合成研究

介绍了磷钼杂多酸的合成。通过正交试验探讨了反应物料量比、三氧化钼浓度、反应温度和反应时间对产物产率的影响。结果表明,最适宜的反应条件为:反应物量比n(三氧化钼)∶n(磷酸)=12∶1.0、反应温度t=70℃、反应时间7 h、三氧化钼与水的质量比1∶8。经红外光谱分析及熔点测定确定所得产品为磷钼杂多酸化合物。并以磷钼杂多酸取代硫酸作催化剂制备乙酸乙醋来研究其催化活性,并与硫酸做催化剂进行对比实验收率为70.75%,超过硫酸催化剂水平。     

The Growth‐Inhibiting Effects of Beef Fatty Acids on MCF‐7 Cells Are Influenced Mostly by the Depot Location and Inconsistently by the Biohydrogenation Intermediate Content

Biohydrogenation intermediates (BHI) including conjugated linoleic acid (CLA) isomers are formed during ruminal biohydrogenation of polyunsaturated fatty acids (PUFA) in ruminants. Although many studies have examined the anticarcinogenic effects of CLA, few studies have reported the anticarcinogenic properties of BHI in their natural form found in dairy and beef fats. The present study compared the growth‐inhibitory effects of fatty acids from beef perirenal fat (PRF) or subcutaneous fat (SCF) with low or high levels of BHI in MCF‐7 human breast cancer cells. Cells were exposed for 72 h to media containing increasing doses (50 to 400 μM) of different beef fat treatments. Fatty‐acid analysis showed that BHI were readily incorporated into cell phospholipids (PL) in a treatment‐dependent manner, but higher BHI in PL did not consistently inhibit growth. Culturing with low‐BHI PRF or high‐BHI PRF did not lead to growth inhibition, but low‐BHI SCF inhibited growth, and inhibition was further increased by high‐BHI SCF. Other classes of fatty acids may, therefore, be interacting with BHI resulting in differential effects on growth inhibition in human breast cancer cells.     

Fatty Acid Profiles in Sunflower Grains During Storage in Different Environments

This study aimed to evaluate the fatty acid profiles of sunflower oil extracted from hybrid grains produced and stored in different environments. The trials were conducted in Teresina (Piauí), Vilhena (Rondônia), and Jaguariúna (São Paulo) in randomized complete block design with 4 replicates. After harvesting, grains from 1 high oleic and 3 traditional hybrids were packed in kraft paper bags and stored in a covered shed and in a cold chamber up to 12 months. The fatty acid profiles were determined by gas chromatography after 0, 4, 8, and 12 months of storage. Analyses of variance were conducted in a split‐plot design, with hybrids being considered as whole plots and storage times as subplots. Tukey's test was performed to compare hybrids and regression analyses for storage times. The initial fatty acid profile of the grains of the same hybrid varied depending on the production location. The grain storage of high oleic and traditional sunflower hybrids during 12 months in covered shed and in cold chamber resulted in little changes in oil fatty acid profiles, regardless of the initial contents. These changes occurred only for linoleic and palmitic acids.     

Fatty Acid Profiles of Oil Obtained from Mid-Oleic Sunflowers Grown in Tropical Region

This study aimed to verify whether the fatty acid profiles of mid-oleic genotypes grown in the tropical region of Brazil fit the Codex Alimentarius and to examine the possibility of using traditional inbred lines to produce high-oleic hybrids. For this purpose, we assessed the fatty acid profile of six mid-oleic hybrids grown in environments with different minimum temperatures during oil formation in the achenes. The tests were conducted between 2015 and 2017 in an experimentally randomized complete block design with four replications. The oleic, linoleic, palmitic, and stearic acid contents were determined using gas chromatography. The mid-oleic hybrids presented varying levels of fatty acids, with oleic acid ranging between 43.6% and 84.6%, linoleic acid between 8.5% and 45.6%, palmitic acid between 3.9% and 5.7%, and stearic acid between 2.2% and 6.2%. Some of the fatty acid values were outside the ranges established by the CODEX STAN 210-1999 and were characteristic of high-oleic type sunflowers. This finding shows that we can take advantage of the potential of combining traditional inbred lines to produce high-oleic hybrids for faster and more economical breeding programs in these environments.     

Quality of Sunflower Oil Obtained in the Main Producing Region of Brazil: Adherence to the Codex Alimentarius

The objective of this work was to evaluate the quality of the oil extracted from sunflower achenes grown in Campo Novo de Parecis, the main producing region of Brazil, to optimize its use by the processing and food industries. In addition, the fatty acid profiles of the oil were checked for their adherence to the CODEX STAN 210–1999. Traditional and high-oleic genotypes were grown between 2014 and 2017 during trials with a randomized complete block experimental design with four replications. The contents of oleic, linoleic, palmitic, and stearic acids were determined using gas chromatography. The fatty acid profiles of traditional genotypes were observed to be outside the ranges established by the CODEX, with an oleic acid content above 39.4% and linoleic, palmitic, and stearic acid values lower than 48.3%, 2.7%, and 5.0%, respectively, as well as high-oleic sunflower oil with a stearic acid content of less than 2.6%. The availability of this information can, on the one hand, positively impact industries and encourage the use of better quality raw materials that are more technologically and nutritionally adequate. On the other hand, the commercialization of sunflower oil with a fatty acid profile outside the ranges established by CODEX can be difficult, because the contents are out of specification due to the climatic conditions in the cropping region.     

质子酸催化合成α-氯代十二酸工艺研究

采用廉价的浓硫酸为催化剂,氧气为自由基捕集剂,以十二酸为原料,经氯化合成α-氯代十二酸。系统考察了反应温度、催化剂用量、氯气流量、氧氯比、反应时间等因素的影响,得到最佳工艺条件:十二酸20 g,在反应温度135℃、催化剂10%、氯气流量50 mL·min-1、vO2/vCl2=1∶2、反应时间3 h,可实现十二酸基本完全转化,目标产物α-氯代十二酸选择性达到94.5%。     

热盐酸缓蚀抑雾剂

在实验室合成的一种咪唑啉类化合物与其它物质复配得到了一种适合于碳钢在高温盐酸中酸洗浸蚀的复合缓蚀抑雾剂。采用失重法和中和滴定法对其性能进行评定 ,实验结果表明 :该缓蚀抑雾剂在 2 0 %盐酸中 ,酸洗温度在常温至 85℃范围内缓蚀率达 90 %左右 ,抑雾率达 85%左右 ,并具有较好的综合性能