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1.
梁明远  刘雄民  李伟光  马丽  沈芳 《应用化工》2010,39(3):314-317,328
采用紫外分光光度分析方法研究了枞酸在聚乙烯膜上的氧化反应,考察了MBP,FMH,DBH,DSB3,DSB65种抗氧剂对枞酸氧化反应的影响,提出了用抗氧化值AO考核抗氧剂的抗氧化能力。实验结果表明,枞酸氧化反应动力学在初期阶段呈表观一级,后期受氧化膜影响不呈表观一级。当反应温度为35,40,45,50,55℃时,5种抗氧剂都表现出不同程度的抗氧化能力,其中MBP,DBH,DSB6抗氧剂的抗氧化能力显著,在35℃下其抗氧化值AO分别是109.92,50.93,209.84。  相似文献   

2.
利用聚乙烯膜微量反应器,在30℃恒温箱中,254 nm紫外光照射下,进行添加了抗氧剂BHA的松香及其衍生品(枞酸和松香季戊四醇酯)的固态光氧化反应。采用紫外分光光度法跟踪监测了它们的光氧化进程;探究了抗氧剂BHA对松香及其衍生产品光氧化反应的影响。结果表明,抗氧剂BHA的添加能有效减缓松香及其产品的光氧化速率,抗氧剂BHA对产品的抗氧化效果顺序从大到小为:松香>枞酸>松香季戊四醇酯。松香添加抗氧剂BHA的用量选择应在5%以内;松香季戊四醇酯中添加抗氧剂BHA的用量选择应在5%~7%之间;枞酸中添加抗氧剂BHA的用量选择应在7%以内。  相似文献   

3.
以脱氢枞酸与氯化亚砜制得脱氢枞酸酰氯,脱氢枞酸酰氯和甘氨酸在超声波作用下生成脱氢枞酰甘氨酸,超声波的固定功率为120 W,讨论了反应温度、时间及反应物的用量比对反应的影响。结果表明,最佳的反应条件为:脱氢枞酸酰氯和甘氨酸物质的量之比为1∶1(摩尔比),反应温度20~25℃,反应时间70 m in,产率可达73.81%。并且对脱氢枞酰甘氨酸钠和脱氢枞酰甘氨酸钾的表面活性进行了测试。  相似文献   

4.
枞酸标准样品的研制   总被引:1,自引:1,他引:0  
研究了从马尾松松香中分离得到的95%纯度的枞酸制备枞酸标准样品,用DB-5毛细管石英柱对枞酸样品进行气相色谱定量分析,并运用统计学分析法检验了标准样品的均匀性。枞酸标准样品的稳定性较好,-16℃下稳定时间达到8个月。  相似文献   

5.
歧化松香的气相色谱和紫外分光光度分析方法比较   总被引:2,自引:0,他引:2  
采用1102型气相色谱仪和紫外分光光度计分别对自制歧化松香产品的组成、含量分析。气相色谱法能够准确、全面地对歧化松香产品进行松香树脂酸含量的分析测定。按照ZB B 72002-1984《歧化松香》,使用两台不同型号的紫外分光光度计对产品中的枞酸和脱氢枞酸含量进行分析测定,选择狭缝宽度为0.1 nm,紫外分光光度法对枞酸含量在0.05%~4.88%、脱氢枞酸含量在41.1%~50.9%之间的歧化松香产品分析较准确。  相似文献   

6.
采用超声波强化反应-结晶耦合的方法单离松香主要成分枞酸,测定了枞酸的恒容燃烧热、熔点和比旋光度,通过UV、GC-MS、NMR对枞酸进行分析鉴定。结果表明,用GR-3500B2氧弹式量热计测定枞酸的恒容燃烧热为–11441.46 kJ mol 1,计算出枞酸的标准摩尔燃烧焓和标准摩尔生成焓分别为–11457.57 kJ mol 1和–699.43 kJ mol 1;用341LC plus微量旋光仪测定枞酸的比旋光度为–105.4;用DSC 6200差示扫描量热仪测得枞酸的熔点和熔化焓分别为450.89 K和19.44 kJ mol 1,计算出枞酸的熔化熵为43.11 J mol 1 K 1。  相似文献   

7.
这种方法的基础是,用Ⅰ—氨基—2萘酚—4磺酸的重氮盐与枞酸型酸反应,然后在490—510mμ下测定所形成偶氮染料的颜色强度。这种反应可以专门用来测定枞酸型酸,也可以用来测定带二烯键的松香酸总量,方法是直接将其异构化为枞酸型酸。在松香改性中,枞酸型酸的含量随着改性强度的增加而减少,因此,改性的程度可以根  相似文献   

8.
《应用化工》2022,(Z2):300-302
利用GC-MS联用仪和GC对印尼松香进行了定性和定量分析,鉴定出7个组分,占总量的97. 11%,其中海松酸型,枞酸型树脂酸及二元羧酸分别占23. 57%,64. 68%,8. 86%。主要成分为山达海松酸,异海松酸,长叶松酸,枞酸和南亚松酸,含量分别为9. 03%,14. 54%,22. 17%,32. 60%,8. 86%。结果表明,印尼松香成分类似我国海南南亚松松香,确定该松香原料来自南亚松。  相似文献   

9.
去氢枞酸甲酯选择性硝化反应的研究   总被引:1,自引:0,他引:1  
采用均匀设计方法深入研究了去氢枞酸甲酯在HNO3-Ac2O-AcOH体系中选择性硝化的反应条件.通过理论计算和实验验证获得去氢枞酸甲酯选择性硝化的较优反应条件如下:n(硝酸):n(去氢枞酸甲酯)为3:1、混合溶剂中乙酐与乙酸的体积比为7:1、反应温度为20℃、反应时间为60 min.此时12-硝基去氢枞酸甲酯和14-硝基去氢枞酸甲酯的总产率由50%提高到84.6%,其中12-硝基去氢枞酸甲酯的产率达到64.0%、14-硝基去氢枞酸甲酯的产率达到20.6%,二者的产率比约为3.1:1.12-硝基去氢枞酸甲酯的反应产率和选择性都明显高于文献报道值.  相似文献   

10.
脱氢枞酸型热塑性树脂成核剂的研究进展   总被引:3,自引:0,他引:3  
综述了热塑性树脂成核剂--脱氢枞酸及其盐类的制备方法、分子结构和晶体的X射线衍射特征,介绍了该类成核剂在聚丙烯、聚乙烯及聚对苯二甲酸二乙酯中的应用方法及效果,认为以松香为主要原料的脱氢枞酸型成核剂的发展应该是利用其分子中的活性基团进行化学改性,或与其他成核剂复合改性,以发挥不同成核剂的协同效应.  相似文献   

11.
紫外光辐射接枝及胺化法制备温敏性聚乙烯薄膜   总被引:1,自引:0,他引:1  
郭世平  陈显辉  王涛 《当代化工》2016,(9):2067-2069
实验探索在水性体系中经紫外光辐射,引发丙烯酸(AAC)在聚乙烯(PE)薄膜表面接枝,并经过胺化反应,在已改性的丙烯酸-聚乙烯(AAC-g-PE)薄膜上继续引入功能团,使改性后的PE薄膜具有温度敏感性。考察了引发剂用量、紫外光照射时间对接枝率的影响,并对不同胺化剂合成产物的温敏效应进行比较,从而达到实验目的。通过红外光谱和尺寸变化率证明丙烯酸接枝在PE表面,胺化反应后,生成聚N-异丙基丙烯酰胺聚合聚乙烯(PNIAAm-g-PE)薄膜和聚N-正丙基丙烯酰胺聚乙烯(NNPA-g-PE)薄膜具有温敏性。  相似文献   

12.
以蒽醌、溴苯等为主要起始原料,通过蒽的1位及9、10位取代,合成了1-甲氧基-9,10-二苯基蒽(MDPA)。改进和优化了各步合成工艺条件:在汞盐催化下,当反应温度为130℃,发烟硫酸浓度为20%~25%,反应时间为1.5 h时,中间体蒽醌-1-硫酸钾收率为53.7%;采用苯基锂与1-甲氧基蒽醌加成后,直接用SnC l2的乙酸水溶液还原,产品收率为68.9%。测试了MDPA在PE农膜中的转光性质。结果表明,将MDPA掺入PE树脂中而形成的蓝光膜能在波长438 nm处光致发光,该波长与植物光合作用所需的蓝光区相吻合;与普通农膜相比,蓝光膜可促进作物生长,使白菜、茼蒿、莴笋等蔬菜产量增加20%左右。  相似文献   

13.
Summary About half of the rosin acids in whole and distilled tall oil consist of abietic and neoabietic acids, as distinguished from hydroabietic acids, dehydroabietic acid, and the pimaric acids. In this respect the tall oil rosin acids are similar to those from gum or wood rosin. This was established by spectrophotometric analysis of the rosin acids from whole tall oil, double distilled tall oil, rosin acids crystallized from tall oil, and rosin acids separated from tall oil by fractional distillation. The rosin acids crystallized from tall oil contained the highest percentage of abietic acid, but the sum of abietic and neoabietic acids was only slightly higher. The rosin acids from acid refined tall oil contained appreciably less abietic and neoabietic acid than the others. Before spectrophotometric analysis the rosin acids were isolated from the tall oils in about 95% yield by cyclohexylamine precipitation.  相似文献   

14.
以聚乙烯蜡和硬脂酸为添加剂,采用水浴加热混合蜡测量滴熔点和粘度,在聚乙烯蜡质量百分含量为0% ~ 15%、硬脂酸质量百分含量为0% ~ 60%范围内,对石蜡的使用性能进行改性研究.实验结果表明,聚乙烯蜡和硬脂酸均对石蜡滴熔点和运动粘度有一定的影响.在聚乙烯蜡添加量为0% ~ 15%的范围内,改性石蜡的性能得到明显改善,其中改性石蜡的滴熔点呈缓慢增高趋势,后保持稳定;当其添加量在3%~5%的范围内,改性石蜡的熔点快速升高.在聚乙烯蜡加入量为3%时加入质量分数为5%~60%硬脂酸进行对比试验.硬脂酸在添加量为5%~25%时,改性石蜡滴熔点呈下降趋势;硬脂酸添加量为25%~60%时,改性石蜡滴熔点上升,但上升效果不明显.  相似文献   

15.
程珏  郑义  杨万泰 《化工学报》2006,57(12):3029-3032
Low density polyethylene film surface-grafted process. Firstly, acrylic acid was grafted to the surface grafting. Secondly, the carboxylic groups in poly (acrylic resorcinol was prepared by a sequential of low density polyethylene by UV photoacid) chains were transferred to acyl chloride groups by the reaction of carboxylic groups with thionyl chloride. The stability of acyl chloride groups in several solvents (alcohol, water, acetone, aqueous NaOH and in N2 atmosphere) was investigated, and N2 atmosphere and acetone were appropriate media to protect acyl chloride groups from side reaction. Finally, resorcinol monomer reacted with acyl chloride to append to the poly(acrylic acid) chains at room temperature. FT-IR ATR was used to characterize the change of carbonyl groups during each step of the grafting process. Furthermore, by the experimental data of gravimetric analysis the grafted resorcinol monomer on the surface of low density polyethylene film was verified to have undergone condensation with acetone further in the resorcinol/acetone solution at 56℃, which might be a useful feature for synthesizing a thermoplastic/thermosetting composition.  相似文献   

16.
利用直接辐射接枝法将丙烯酸接枝于聚乙烯膜可改善其性质,在体系中加入适量阻聚剂可使接枝反应顺利进行,加入无机酸可促进接枝反应,基材的结晶度和厚度对接枝反应有很大影响。此外,还利用红外技术定性定量表征了接枝物,并用扫描电镜观察了接枝物的形态。  相似文献   

17.
The effect of ultraviolet light irradiation on the characteristics of the polyethylene (PE) surface was investigated by the quartz crystal microbalance (QCM) technique. The PE film was prepared on the gold electrodes of the QCM by spin-coating from the solution and then was treated by the excimer UV lamp in ambient air. The changes in the hydrophilic properties, moisture adsorption, and water retention of the PE film due to the UV irradiation were determined from the frequency change of the QCM. To evaluate the detergency of the PE film, stearic acid as model oily soil was deposited onto the PE film formed on the QCM by the Langmuir-Blodgett (LB) technique, and was ultrasonically cleaned in aqueous detergent solutions containing ethanol or surfactant. The removal efficiency obtained from the frequency change of the QCM was found to increase considerably after the UV irradiation. From independently determined contact angles and the surface free energy components of the PE film, the free energy change resulting from the penetration of the detergent solution between stearic acid and PE in the zone of contact was calculated. Good relation was found between the removal efficiency and the free energy change, indicating that the increase in the detergency of the PE surface by UV irradiation was explained by surface energetics.  相似文献   

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