摘要
通过分析总结前人的研究成果及经验,从黄原胶固有的分子结构出发,分析了黄原胶的高温降解机理,论述了黄原胶高温稳定性的影响因素。分析结果表明,当温度高于构象转变温度时,黄原胶分子由原来有序的稳定的二维结构变成杂乱无序的结构,使其主链暴露出来,更容易受到外部自由基和酸碱的攻击而变得不稳定;氧是黄原胶发生自由基氧化还原反应的主要原因,因此加入抗氧剂可提高黄原胶的热稳定性;一价盐尤其是甲酸钾、KCl等含K+的碱金属盐类,能够提高黄原胶的构象转变温度;在酸性和碱性pH值条件下,黄原胶都容易发生水解反应,因此应尽可能地使pH维持在中性。
Xanthan gum is a kind of biopolymer produced by ferment of microbes.The aqueous solutions of that have great viscosity and shear thinning property making it widely used as viscosity agent in oilfield.But for the bad performance of high temperature stability,it can not be used in high temperature and high pressure deep wells.This article analyzed the results of research and summarized the effects on high temperature stability of xanthan gum,and drew a conclusion of that the effects are molecular structure,side chain,substituents,pH value,salinity and dissolved oxygen in solution.
出处
《钻井液与完井液》
CAS
2011年第6期77-80,97,共4页
Drilling Fluid & Completion Fluid
关键词
黄原胶
高温稳定性
构象转变温度
分子结构
PH值
盐
抗氧剂
Xanthan gum
High temperature stability
Conformation transition temperature
pH
Salinity
Molecular structure
Antioxidant
