新型MA/AA/HEMA三元共聚物阻垢剂的合成及反应条件的确定

以马来酸酐(MA)、丙烯酸(AA)和甲基丙烯酸羟乙酯(HEMA)为单体,亚硫酸氢钠-过硫酸铵为引发剂,叔丁醇为分子量调节剂,采用水溶液自由基聚合法,合成MA/AA/HEMA新型三元共聚物阻垢分散剂,并通过正交实验测试法得出其最佳合成条件。通过静态沉淀抑制法对三元共聚物的阻垢性能进行评价,共聚物投加量为4mg/L时,对CaCO_3的阻垢率最佳,达到93.72%。利用红外光谱和扫描电子显微镜对共聚物的结构进行分析,共聚物结构中具有羧基、酰胺基、酯基和磺酸基等官能团,且具有较大的比表面积使得凝聚分散作用抑制CaCO_3沉淀容易进行。     

MA/AA/AM/AMPS四元共聚物的合成及其对硫酸钙和碳酸钙的阻垢性能

以马来酸酐(MA)、丙烯酸(AA)、丙烯酰胺(AM)和2-丙烯酰胺-2-甲基丙磺酸(AMPS)为原料,通过自由基溶液共聚合法,合成了MA/AA/AM/AMPS四元共聚物阻垢剂。红外光谱(FT-IR)结果表明共聚物分子链上同时含有羧酸基、酰胺基和磺酸基等基团;扫描电镜(SEM)分析表明MA/AA/AM/AMPS抑制了碳酸钙和硫酸钙垢的生长。探讨了共聚物用量、钙离子浓度、体系pH值和温度对MA/AA/AM/AMPS阻碳酸钙和硫酸钙垢的影响。结果表明,合成产物对碳酸钙和硫酸钙具有优良的阻垢性能,且适用于高温循环水处理。     

环境友好型AA/MA/HEMA共聚物阻垢剂的合成及阻垢性能研究

以马来酸酐(MA)、丙烯酸(AA)和甲基丙烯酸羟乙酯(HEMA)为单体,通过水溶液自由基聚合的方法合成新型三元共聚物阻垢剂,共聚物的数均分子量为1259左右,属于分布较窄的过渡区分子量聚合物。对共聚物进行红外光谱和扫描电子显微镜分析可知:共聚物中含有分散阻垢所需的羧基、酰胺基和磺酸基等官能团,晶格畸变和络合増溶是共聚物抑制沉淀的主要作用机理。通过与四种常用绿色环保阻垢剂阻垢性能的对比试验,探讨了共聚物的投加量、钙离子质量浓度、水样温度等对共聚物阻垢性能的影响。结果表明:共聚物投加量为3mg/L,水温80℃,钙离子质量浓度480mg/L时,阻垢率达到91.35%。共聚物对碳酸钙的整体阻垢性能优于常规阻垢剂,特别适用于高温、中高硬的工业循环冷却水。     

一种改性磺化苯乙烯/马来酸酐共聚物的合成及阻垢杀菌性能研究

以马来酸酐(MA)、对苯乙烯磺酸钠(SS)和N,N-二甲基-N-苄基-N-丙烯酸酯基氯化铵(DA)为单体,K2S2O8作为引发剂,在水相中合成共聚物阻垢剂P(MA-SS-DA)。通过正交实验,确定了合成P(MA-SS-DA)的最佳条件为:n(MA)∶n(SS)∶n(DA)=1∶0.6∶0.2,聚合温度为80℃,K2S2O8用量为单体总量的1.0%。采用静态阻垢法研究P(MA-SS-DA)对硫酸钙垢沉积的抑制作用。结果表明,共聚物对CaSO4的阻垢率为62%,24h后的杀菌率可达到60%。     

低磷环保循环水处理阻垢缓蚀剂的复配、性能与机理

为解决工业循环冷却水系统的腐蚀与结垢的问题,选用生物降解性良好的羧乙基硫代丁二酸（CETSA）、丙烯酸-2-丙烯酰胺-2-甲基丙磺酸共聚物（AA/AMPS）、聚环氧琥珀酸（PESA）、2-膦酸基丁烷-1,2,4-三羧酸（PBTCA）、月桂酰肌氨酸钠（LS）、甲基苯并三氮唑钠盐（TTA-Na）和七水硫酸锌作为复合阻垢缓蚀剂的组分进行复配,采用GB/T 16632-2008和GB/T 18175-2014测试了其缓蚀及阻垢性能。结果显示：较优的阻垢缓蚀剂组合为CETSA 10 mg/L,AA/AMPS 14 mg/L,PESA 20mg/L,PBTCA 4 mg/L,LS 10 mg/L,TTA-Na 10 mg/L,七水硫酸锌(以Zn²⁺计) 1 mg/L,其阻垢率为96.35%,腐蚀速率为0.007 2 mm/a,缓蚀率为99.68%,其缓蚀阻垢性能优良,且对环境友好。电化学测试结果表明复合阻垢缓蚀剂为阴极型缓蚀剂。SEM观测表明复合阻垢缓蚀剂能在碳钢表面形成保护膜,并能吸附在碳酸钙晶体上,使其无法正常长大。     

原子转移自由基聚合制备端磺酸基PS及其与表面阳离子化的SiO2静电自组装研究

以2-溴异丁酸对磺酸基苯乙酯为引发剂引发苯乙烯发生原子转移自由基聚合,得到的聚合物与NaOH反应转化为端基为磺酸钠的PS(PS-SO3Na).然后采用静电组装方法将PS-SO3Na与表面阳离子化的SiO2胶体(SiO2-CBAFS)进行静电组装,得到表面构筑了高分子刷的有机一无机纳米粉体及单层膜.采用红外、核磁表征了PS-SO3Na的结构,并用红外、热失重、接触角研究了组装体系的结构、组装量及表面行为.研究表明,采用2-溴异丁酸对磺酸基苯乙酯可以引发苯乙烯聚合得到PS-SO3Na,采用静电组装的方法可以成功地在表面阳离子化的SiO2-CBAFS上构筑组装量高达34.4%的高分子刷,并且高分子刷的表面水接触角达到75.3°;组装体系的组装量、表面水接触角均随聚合物溶液浓度的增加而下降;当外界环境不同时,其表面水接触角也发生相应的变化.     

多羟基阻垢剂PTMAS的研制与应用

为解决塔河油田在注水开发过程中因地层水不配伍而出现的碳酸垢和硫酸垢结垢问题,以自制三羟乙基烯丙基溴化铵(THAAB)、马来酸酐(MA)和2-丙烯酰胺基-2-甲基丙磺酸(AMPS)为反应单体,采用水溶液聚合,制得了多羟基聚合物型阻垢剂聚三羟乙基烯丙基溴化铵/马来酸酐/2-丙烯酰胺基-2-甲基丙磺酸(PTMAS)。对产物进行红外光谱与凝胶色谱分析,结果表明其分子结构符合预期设计且分子量大小适中,分子量在2×104~5×104之间,适于作为聚合物阻垢剂。热重分析证明其抗温性能较强,在250℃之前质量保留率高达80%,并未出现大的质量损失。在碳酸钙阻垢实验中,PTMAS添加量不低于25mg/L,适用温度为20~80℃,pH不超过10,有效阻垢时间不小于18h,阻垢率可高达92%,表明PTMAS的适用工况极为宽泛。室内实验结果表明对于硫酸钙、硫酸钡与硫酸锶垢的析出成垢亦有良好阻垢效果。     

改性聚环氧琥珀酸衍生物的合成与阻垢性能

以顺酐环化、聚合产物聚环氧琥珀酸(PESA)和硫脲(CSN)为原料合成了一种聚环氧琥珀酸衍生物(CSN-PESA),利用红外光谱和核磁共振谱对聚环氧琥珀酸衍生物的结构进行了表征,测定了聚环氧琥珀酸和硫脲不同比例时产物的分子量;探讨了聚环氧琥珀酸衍生物的阻垢性能、分散氧化铁的性能和生物降解性能;利用红外光谱和扫描电镜对垢的晶型(形)进行了研究。结果表明,当PESA与CSN的质量比为8∶4时,产物的分子量达到了581左右,其阻垢和分散效果最好;在钙离子浓度为400 mg/L、碳酸氢根离子浓度为800 mg/L的介质中,当聚环氧琥珀酸衍生物用量为8 mg/L时,阻垢率达到95%以上;当n(Ca2+)=150 mg/L,n(Fe2+)=10 mg/L,加药量为20 mg/L时,其上清液最小透光率为75%。结果表明,改性聚环氧琥珀酸衍生物对碳酸钙垢有晶格扭曲的作用,可把稳定的方解石转化为球霰石,表现出良好的阻垢分散性能和可生物降解性能。     

PTA-IA-AMPS三元功能共聚物的合成及缓蚀阻垢性能研究

以马来酸酐(MA)、乙醇胺(EA)、衣康酸(IA)以及2-丙烯酰胺-2-甲基丙烷磺酸(AMPS)为单体,过硫酸铵和次亚磷酸钠为引发剂,采用水溶液自由基聚合制备PTA-IA-AMPS三元功能共聚物。通过正交优化和验证实验确定最佳合成条件。采用静态阻垢法和旋转挂片法分别测试合成产物的阻垢和缓蚀性能。结果表明,共聚单体的摩尔比(n_(IA)∶n_(PTA)∶n_(AMPS))为2.5∶1∶0.1、引发剂过硫酸铵和次亚磷酸钠用量分别为单体总质量的8%和20%、反应温度为90℃且反应时间4 h,合成的PTA-IA-AMPS共聚物性能最佳;用量为30 mg/L时,阻垢率可达90.83%,缓蚀率99.40%,属于抑制阴极为主的阴极型缓蚀剂,性能优良。     

复合缓蚀阻垢剂对模拟循环冷却水中Q235碳钢的缓蚀与阻垢性能

为寻找性能更优的缓蚀阻垢剂,采用静态失重、静态阻垢、电化学测试、X射线粉末衍射(XRD)、扫描电镜(SEM)等方法,研究了聚环氧琥珀酸(PESA)、羟基乙叉二膦酸(HEDP)及其复合物对模拟循环冷却水中Q235碳钢的缓蚀与阻垢性能。结果表明:复合缓蚀阻垢剂对Q235碳钢的缓蚀率和阻垢率均达到90%以上,其缓蚀、阻垢性能明显优于单组分PESA和HEDP;复合缓蚀阻垢剂是以抑制阴极反应为主的缓蚀剂,能很好地发挥各组分间的协同作用,在碳钢表面形成保护膜,抑制其在循环冷却水中发生腐蚀;复合缓蚀阻垢剂有助于Ca CO3垢样的分散和球霰石晶型的形成,起到较好的阻垢分散作用。     

马来酸酐三元共聚物的阻垢、分散及缓蚀性能

研究了以水为溶剂、过硫酸盐作引发剂合成的马来酸酐－烯丙基磺酸钠－丙烯酰胺（MA－SAS－AM）三元聚合物阻垢的阻垢、分散及缓蚀性能，测定了阻垢剂浓度、溶液pH值、Ca^2 浓度及介质温度对阻垢效果的影响。结果表明，MA－SAS－AM对磷酸钙具有优异的阻垢性能，对锌盐具有良好的稳定作用，对碳酸钙阻垢效果较差。pH=9时，12mg/L的阻垢剂对磷酸钙垢的抑制率达97％，对锌盐为69％。聚合物对氧化铁的分散效果好，对碳钢具有一定的缓蚀性能。     

水体系中合成羟化聚天冬氨酸及其阻垢性能

以马来酸酐和碳酸铵为原料,通过薄层聚合制备了聚琥珀酰亚胺(PSI);在水介质中采用乙醇胺与PSI进行反应,合成了羟基改性的聚天冬氨酸衍生物——羟化聚天冬氨酸(HPASP)。用红外光谱和核磁共振对产物结构和组成进行了表征;比较了聚天冬氨酸和HPASP的阻垢性能。结果显示,HPASP对磷酸钙具有更好的阻垢性能,在HPASP含量为12 mg/L时,阻垢率可以达到63.8%,是相同含量下聚天冬氨酸阻垢率的2.5倍。     

丙烯酸-丙烯酸羟丙酯-乙烯磺酸钠共聚物及其复配物的阻垢、缓蚀性能

为了简化已有阻垢缓蚀荆的制造工艺,降低生产成本,以水为溶剂,过硫酸盐为引发剂,用乙烯磺酸钠(SVS)、丙烯酸羟丙酯(HPA)和丙烯酸(AA)合成了兼具阻垢分散特性和缓蚀性能的AA-HPA-SVS共聚物,按国家标准对其阻垢和缓蚀性能进行了研究.结果表明:AA-HPA-SVS三元共聚物对中性介质中CaCO<,3>和Ca<,...     

Scanning thermal lithography of tailored tert-butyl ester protected carboxylic acid functionalized (meth)acrylate polymer platforms

In this paper, we report on the development of tailored polymer films for high-resolution atomic force microscopy based scanning thermal lithography (SThL). In particular, full control of surface chemical and topographical structuring was sought. Thin cross-linked films comprising poly(tert-butyl methacrylate) (MA(20)) or poly(tert-butyl acrylate) (A(20)) were prepared via UV initiated free radical polymerization. Thermogravimetric analysis (TGA) and FTIR spectroscopy showed that the heat-induced thermal decomposition of MA(20) by oxidative depolymerization is initially the primary reaction followed by tert-butyl ester thermolysis. By contrast, no significant depolymerization was observed for A(20). For A(20) and MA(20) (at higher temperatures and/or longer reaction times) the thermolysis of the tert-butyl ester liberates isobutylene and yields carboxylic acid groups, which react further intramolecularly to cyclic anhydrides. The values of the apparent activation energies (E(a)) for the thermolysis were calculated to be 125 ± 13 kJ mol(-1) and 116 ± 7 kJ mol(-1) for MA(20) and A(20), respectively. Both MA(20) and A(20) films showed improved thermomechanical stability during SThL compared to non cross-linked films. Carboxylic acid functionalized lines written by SThL in A(20) films had a typically ~10 times smaller width compared to those written in MA(20) films regardless of the tip radius of the heated probe and did not show any evidence for thermochemically or thermomechanically induced modification of film topography. These observations and the E(a) of 45 ± 3 kJ mol(-1) for groove formation in MA(20) estimated from the observed volume loss are attributed to oxidative thermal depolymerization during SThL of MA(20) films, which is considered to be the dominant reaction mechanism for MA(20). The smallest line width values obtained for MA(20) and A(20) films with SThL were 83 ± 7 nm and 21 ± 2 nm, whereas the depth of the lines was below 1 nm, respectively.     

可生物降解聚天冬氨酸阻垢剂性能研究

用极限黏度法测定合成聚天冬氨酸的粘均分子量,用静态阻垢法评价聚天冬氨酸的性能,用摇床法检验聚天冬氨酸的生物降解性。结果表明,粘均分子量为10000 g/mol的聚天冬氨酸阻垢效果最佳,对CaCO3、CaSO4、BaSO4垢的阻垢率都达到90%以上,生物降解率也在70%以上。     

PSS-VS共聚物掺杂PEDOT的合成与表征

以苯乙烯磺酸钠(SSS)和乙烯磺酸钠(SVS)的共聚物PSS-VS为掺杂剂,过硫酸铵(APS)为氧化剂,采用化学氧化法制备了PEDOT/PSS-VS分散体,研究了PSS-VS的共聚比、分子量和用量等因素对PEDOT/PSS-VS导电性能及平均粒径的影响,分析了PEDOT/PSS-VS粒子形成过程。结果表明,SSS/SVS共聚摩尔比为5/5,单体与APS摩尔比为60时制得的PSS-VS掺杂PEDOT具有较好的导电性和分散稳定性,SO3-/EDOT=2,APS/EDOT=1.5,PEDOT/PSS-VS固含量为2.8%时制得的PEDOT/PSS-VS电导率可达11.74S/cm,分散体平均粒径为447nm。     

磷酸盐玻璃型阻垢剂的性能评估及溶解机理研究

成功地制备了一种能在水中定量溶解的磷酸盐玻璃阻垢剂．在３０℃时,其阻垢率达９０％．利用比色法测量出与阻垢效率有直接关系的正磷酸根离子（简称正磷）和聚磷酸根离子（简称聚磷）浓度,并据此对磷酸盐玻璃阻垢剂的阻垢性能和控释机理进行了研究,探讨了阻垢剂在溶解过程中发生的水解和水化反应．     

Electrospun crosslinked polyvinyl alcohol membrane

The electrospinning of polyvinyl alcohol (PVA) was performed with maleic anhydride (MA) as a cross linker to fabricate slightly soluble nanofiber membrane. The solubility, morphology and thermal behavior of electrospun PVA and PVA/MA membranes were characterized by water durability test, scanning electron microscope (SEM) and differential scanning calorimeter (DSC), respectively. Water durability test demonstrated that 8% PVA/MA (20/1, mole/mole) membrane had the least average mass loss and standard deviation. SEM images showed that fibers in PVA/MA membrane had a larger average diameter compared to those in PVA membrane. DSC investigated that crystal structure was formed in PVA/MA membrane. The results show that rapid evaporation of water and high electric field during electrospinning process may promote crosslinking of PVA and MA.     

Rat palatability,pharmacodynamics effect and bioavailability of mefenamic acid formulations utilizing hot-melt extrusion technology

Abstract

Mefenamic acid (MA) has been reported as a weakly soluble drug which presents weak in vivo absorption upon oral administration using conventional formulations. Solid dispersions (SDs) have been investigated extensively in literature for enhancing the solubility and bioavailability of weakly-soluble molecules. Hence, the aim of proposed study was to prepare MA novel formulations in the form of SDs using hot-melt extrusion technology in order to enhance its palatability, bioavailability, and pharmacodynamics effects/anti-inflammatory efficacy. Various SDs of MA were prepared using hot-melt extrusion technology, characterized physically and investigated for dissolution tests. Optimized SD formulations of MA were being subjected to palatability, pharmacodynamics, and pharmacokinetic studies in rats. Optimized SD of MA showed significant rat palatability tastes as compared with pure and marketed MA (p?<?.05). Anti-inflammatory efficacy of 20% SD and 25% SD of MA was found to be 86.44 and 89.83%, respectively, in comparison with 74.57 and 78.24% by pure MA and marketed MA, respectively. The anti-inflammatory efficacy of optimized SD was found to be significant as compared with pure and marketed MA (p?<?.05). The oral absorption of MA from optimized 20% SD was also noted as statistically significant as compared with pure MA (p?<?.05). The relative bioavailability of MA from 20 and 25% SDs was 2.97 and 2.24-folds higher than pure MA. The results of this study suggested that SDs prepared using hot-melt extrusion technology are capable to enhance palatability, anti-inflammatory efficacy, and oral bioavailability of MA in comparison with pure drug.