Association of ethylene vinyl acetate copolymer in dilute solutions. V. Stability and pour point depression to wax solutions

The stability of two kinds of aggregation states of ethylene vinyl acetate (EVA) copolymer in dilute solution of 1,2‐dichloroethane has been investigated by viscometry. It was found that good storage‐time, shearing, and dilution resistance were displayed for both states of EVA molecule with intra‐ and interchain association. And for the pour point depression of wax solution doped with EVA, the EVA in intrachain aggregation state was better than the EVA in interchain aggregation state. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 836–841, 2000     

润滑油降凝剂T818B的合成及其降凝作用

通过先酯化后聚合的方法合成了润滑油降凝剂T818B(醋酸乙烯-富马酸酯高聚物),考察了该降凝剂对国内几种主要基础油的降凝效果,并探讨了其降凝机理。结果表明,当加剂量为3~5 g/kg时,T818B降凝剂对环烷基基础油具有很好的降凝作用,而其对石蜡基基础油的降凝效果不明显;T818B的降凝机理是醋酸乙烯-富马酸酯高聚物分子改变了环烷基润滑油中分子的结晶方向,使其难于聚集形成三维网状结构,从而起到了降凝作用。     

润滑油降凝剂T818C的合成及其降凝作用

本文研究了润滑油降凝剂T818C（醋酸乙烯-富马酸酯高聚物）的合成,考察了该降凝剂对国内几种主要基础油的降凝效果,并探讨了其降凝机理。结果表明当加剂量为3g／kg～5g／kg时,T818C降凝剂对环烷基基础油和石蜡基基础油均具有很好的降凝作用。     

蓖麻油基润滑油降凝剂的合成

以蓖麻油(CO)、甲基丙烯酸甲酯(MMA)为原料,偶氮二异丁腈(AIBN)为引发剂,甲苯作为溶剂,无水无氧条件下合成了蓖麻油-甲基丙烯酸甲酯共聚物。利用FTIR表征了蓖麻油-甲基丙烯酸甲酯共聚物的结构,用凝胶渗透色谱(GPC)测定了该聚合物的相对分子质量及其分布,并对其降凝性能进行了评价。结果表明：当m(CO):m(MMA)= 1:1、引发剂AIBN用量（引发剂用量占单体总质量的百分数）为0.25%、反应时间为8 h、反应温度为80 ℃时,收率为59.20%,聚合物相对分子质量为2.722×105,相对分子质量分布较窄（PDI=1.51）。且共聚物对润滑油具有一定降凝效果,当共聚物添加量（聚合物质量占油品质量的百分数）为0.5%时,凝点(SP)可降低10 ℃ (ΔSP=10 ℃)。     

EVA型柴油低温流动性能改进剂的研制

制备了EVA型柴油低温流动性能改进剂,对影响聚合过程的四个主要因素——聚合压力、反应温度、引发剂含量以及醋酸乙烯酯含量分别进行了考察,获得了其影响聚合产物粘度、酯含量和降低冷滤点效果的规律;同时利用XRD和DSC初步探讨了该降凝剂的降凝机理。     

柴油降凝剂研究进展

本文综述了国内外柴油降凝剂的研究开发概况,降凝剂的种类及柴油降凝剂的复配研究,并对我国柴油降凝剂研制与开发提出了几点建议.     

原油降凝剂的合成研究及初步实验

合成了丙烯酸高碳醇酯 ,并用其与顺丁烯二酸酐、苯乙烯进行了三元共聚得降凝剂A ,然后再和高级脂肪胺进行胺解反应得到高效原油降凝剂B ,在大港油田的原油中分别加入A和B降凝剂 2× 1 0 -4使原油凝固点分别下降 7℃和2 0℃。加入A和B降凝剂 2× 1 0 -4于任丘、大庆油田中也有明显的降凝作用。同时还对聚合、胺解条件进行了研究 ,当单体物质的量之比为 9∶1∶1在 80℃反应 7h后与高级脂肪胺进行胺解 ,降凝效果最好。     

聚丙烯酸十八酯降凝剂对合成蜡油结蜡特性影响的研究

采用自主研发的Couette结蜡装置研究了聚丙烯酸十八酯（POA）降凝剂对合成蜡油体系结蜡特性的影响。通过对结蜡层表面样（远离结蜡筒）和底部样（靠近结蜡筒）的宏观观察、DSC放热、气相色谱及蜡晶微观结构的分析发现：POA的加入降低了蜡油体系的结蜡速率,加快了蜡油体系的老化速率,且在一定浓度范围内（50～200 μg·g^-1）导致了径向不均质蜡沉积结构的形成,从结蜡层表面到底部含蜡量逐渐升高,但在较高加剂浓度（400 μg·g^-1）时径向不均质蜡沉积结构消失;POA的加入使得结蜡层表面样和底部样的临界碳数（CCN）都由C₂₄升高到C₂₅,但结蜡层底部样与表面样相比低碳数正构烷烃（≤ C₂₅）有所减少,高碳数正构烷烃（≥ C₂₆）有所增加;随着油样中POA浓度的增大,结蜡层表面样与底部样的蜡晶形貌由针状蜡晶逐渐转变为片状蜡晶,且蜡晶尺寸逐渐变大,结构更为致密。     

原油降凝剂的合成及性能研究

针对我国原油含蜡量较高的特点,采用在原油中加入化学降凝剂的方法,对原油降凝。以高活性聚异丁烯为主要原料,先与苯进行烷基化反应得到聚异丁烯烷基苯,再以浓硫酸为磺化剂进行磺化反应,制得的烷基苯磺酸经中和反应制得烷基苯磺酸盐原油降凝剂。红外光谱分析表明,产物为预期产物。用偏光显微镜研究了加剂前后晶体形态,并探讨了降凝机理。通过对产物与大庆原油进行的降凝效果的测定,证实合成的产物在大庆原油中加入量为0.6%时降凝效果最好,降凝幅度为8℃。     

Ultrasonic disassociation of EVA random copolymer in dilute solutions

Ultrasonic disassociation of the ethylene–vinyl acetate (EVA) random copolymer in 1,2‐dichloroethane (DCE), cyclohexane (CYH), and their solvent mixtures was investigated using viscometry and dynamic laser light scattering (DLLS). It was found that the disassociation of the EVA aggregates in solutions increases with increasing the time and intensity of ultrasonic shearing and approaches invariant finally. This phenomenon is especially marked for the EVA copolymer with low vinyl acetate (VA) content in the polar solvent of DCE at higher concentration and lower temperature. This is attributed to disassociation of the ethylene segment of the EVA random copolymer in dilute solutions. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2798–2802, 2001     

新型原油降凝剂的绿色合成与复配研究

将一种电荷转移配合物（CTC）与丙烯酸十八酯（SA）发生聚合反应,合成出一种性能优良的降凝剂（CS）,在加量为900μg/g时,可使长庆原油的凝点下降10℃;CS与T-1804A复配比例为1∶1时,可使长庆原油凝点下降14℃。通过差示扫描量热,研究了降凝机理及复配机理。结果表明,降凝剂的加入使得系统的热能发生改变,增加了相变能。     

柴油降凝剂研究的进展

叙述了国内外柴油降凝剂的研究开发概况，提出了对降凝剂作用机理的新看法以及柴油低温流动改进剂研究开发的方向     

含氮原油降凝剂的合成及评价

以马来酸酐(MA)和丙烯酸十八酯(OA)为单体进行聚合,并用十二胺接枝改性,合成了丙烯酸十八酯-马来酸双十二烷基酰胺梳型共聚物(POMN)。用红外光谱对聚合物进行了表征,并考察了该降凝剂对长庆含蜡原油的降凝减黏效果。结果表明,当n(MA):n(OA)=1:4,加剂量为300μg/g,加剂温度为60℃时,降凝效果较好,原油凝点降低13℃,原油低温黏度也大大降低。为了进一步扩大降凝效果,进行了复配实验。结果表明,POMN与乙烯-醋酸乙烯酯(EVA)按质量比为1:1复配,效果最佳,降凝幅度可达17℃,大大改善了含蜡原油的低温流动性能。     

原油降凝剂中间体的合成及处理

报道了原油降凝剂中间体的合成及如何清除中间体中阻聚剂的新方法。     

国内柴油降凝剂研究现状及前景分析

简述了柴油降凝剂作用机理及国内外柴油降凝剂发展历程,讨论了国内柴油降凝剂市场现状及研究进展,对今后国内柴油降凝剂的发展进行了分析并提出了建议。     

Synthesis and characterization of novel pour point depressants based on maleic anhydride‐alkyl acrylates terpolymers

The (Docosanyl acrylate‐co‐(octadecyl or hexadecyl acrylate)‐co‐maleic anhydride) terpolymers were prepared using different compositions of the used alkyl acrylates (namely, 90 : 10, 70 : 30, 50 : 50, 30 : 70, and 10 : 90) (DCA‐ODA)/(MA) or (DCA‐HDA)/(MA). The efficiency of these terpolymers as pour point depressants was discussed. Two western desert waxy crude oils with different wax content were used for evaluation. Correlation between pour point depression efficiency and rheological properties were performed. Rheological parameters were also computed and discussed. It was observed that the synthesized terpolymers showed non‐Newtonian pseudoplastic relationships at different concentrations of synthesized terpolymeres with monomer feed ratios of (DCA‐ODA (1 : 1))/(MA) or (DCA‐HDA (1 : 1))/(MA) = 90/10 mole %. This ratio showed a good ability to disperse wax crystals and improve the flow behaviors of tested two crude oils even at low temperatures below their pour points. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

AE-MA型原油降凝剂的制备及效果评价

以甲基丙烯酸、混合醇、马来酸酐为原料,采用"先酯化-后聚合"的方法,合成一种新型原油降凝剂甲基丙烯酸混合醇酯-马来酸酐共聚物(AE-MA)。实验表明,最佳酯化条件为:n(甲基丙烯酸)∶n(混合醇)=1∶1.25、n(十二醇)∶n(十四醇)∶n(十六醇)=3∶6∶1,w(溶剂)=100%,w(催化剂)=1.5%;最佳聚合反应工艺条件为:n(马来酸酐)∶n(甲基丙烯酸混合醇酯)=1∶1,w(引发剂)=0.75%,聚合时间3.5 h,聚合温度80℃。将最佳条件下合成的产物按1.59%(质量分数)的剂量加入到盘锦原油中,原油凝点最多可降低11℃。     

A regular,hydrophobically modified polyampholyte as novel pour point depressant

A new regular polyampholyte, namely poly(N,N‐diallyl‐N‐octadecylamine‐alt‐(maleic acid)), was studied as an additive to crude oil. The amphiphilic polyampholyte proved to be an efficient pour point depressant, to inhibit the deposition of wax, and to improve the viscosity of waxy crude oil from the Akshabulak oilfield (Western Kazakhstan). On optimizing the concentration of the polymer, both the kinematical viscosity and the pour point of waxy crude oils were found to be strongly decreased. The morphology of the paraffin aggregates formed was compared before and after heat treatment of the waxy crude oils, in the presence and the absence of the polymer. The rheological characteristics of the waxy crude oil were markedly improved, in particular, by decreasing the plastic viscosity and the yield stress values upon addition the polymer. The inhibition of wax deposits in the presence of the amphiphilic polyampholyte was interpreted in terms of its interference with the wax crystallization process because of the formation of inverse micellar structures. Although the interaction of the cationic and the anionic groups on the polymer backbone stabilizes the smaller size of the aggregates, the hydrophobic side chains of the polymer provide nucleation sites and cocrystallize with the paraffins, thus modifying the paraffin crystal structure. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 2101–2108, 2005     

英旺油田高含蜡原油降凝剂筛选及现场应用

英旺油田长8油层高131原油具有凝固点较高（17℃）,高含蜡量13．58％特点,运用单一药剂对其降凝效果不明显,分散剂和添加剂复配可有效降低该储层原油凝固点。在添加剂最佳浓度为0．5％,分散剂最佳浓度为5％时,可使长8储层原油凝固点从27℃降低到4．5℃。现场试验表明,采出液凝点均已降低到5℃以下,原油流动性也很好,产量有所增加且稳定。     

Polymeric additives for pour point depression of residual fuel oils

Esters of styrene-maleic anhydride copolymers were synthesised by reacting styrene with maleic anhydride and esterifying the product with fatty alcohols. The resulting copolymers were purified and tested as pour point depressants for residual fuel oils. Comparative evaluation of these esters of styrene-maleic anhydride copolymers with some commercial additives showed their good activity.