盐浓度对交联聚合物线团形态的影响  

The Influence of Salt Concentration on the Dimension of Linked Polymer Coils in Solution

作　　者：董朝霞[1] 吴肇亮[1] 林梅钦[1] 李明远[1] 

机构地区：[1]石油大学化工学院,北京102249

出　　处：《油田化学》2002年第1期80-84,共5页Oilfield Chemistry

基　　金：重质油加工国家重点实验室开放基金资助项目"交联聚合物溶液性质研究"(项目编号 2 0 0 0 13)

摘　　要：用核孔膜过滤法 (过滤体积对过滤时间作图 )、动态光散射法 (DLS)和扫描电镜法 (SEM )研究了交联反应前后盐 (NaCl)浓度变化对低浓度HPAM与AlCit形成的交联聚合物溶液 (LPS)中交联聚合物线团 (LPC)形态的影响。所用HPAM相对分子质量 1.1× 10 7～ 1.4× 10 7,LPS中HPAM与Al的质量比 2 0∶1,HPAM浓度 0 .1或 0 .2 g/L ,交联反应温度 40℃ ,时间 7天。实验结果表明 :①LPC的平均水力半径Rh(DLS测定值 )随交联反应时盐浓度的增大先减小后增大 ,盐浓度由 0 .5 g/L增加到 2 g/L时Rh 由 45 0nm迅速减小到 2 5 0nm ,盐浓度增加到 2 0 g/L时Rh达到最小值 16 0nm ,此后随盐浓度的继续增加Rh 有所增大 ;盐浓度 0 .5和 2 .0 g/L时Rh 的SEM测定值分别为45 0和 2 5 0nm ,与DLS结果一致。②交联反应完成后改变LPS的盐浓度 ,也可改变LPC的Rh 值 ,但改变幅度较小 ;盐浓度 0 .5 g/L时形成的LPS ,当盐浓度增加至 2 g/L时 ,Rh 值由 45 0nm减小至 35 9nm ,大于盐浓度 2 g/L时形成的LPS的Rh 值 (2 46nm) ;盐浓度 2 g/L时形成的LPS ,当盐浓度减少至 0 .5 g/L时 ,Rh 值由 2 46nm增大至32 6nm ,小于盐浓度 0 .5g/L时形成的LPS的Rh 值 (4 5 0nm)。用盐浓度改变引起LPC水化层厚度改变 ,线团收缩或舒张解释盐浓度改变时Rh 测定值的?The influence of salt(NaCl) concentration on the size of intramolecular crosslinked polymer coils in a so called linked polymer solution (LPS), or a colloidal dispersion gel, comprising of HPAM with M=1.1×10 7-1.4×10 7 and Al citrate is investigaled by constructing curves of filtration volume vz filtration time through microporous filter (Nucleopore membrane) at low pressures, by dynamic light scattering (DLS) and SEM. The mass ratio of HPAM to AlCit in LPS-20∶1 and the crosslinking is conducted at 40℃ over 7 days. The experimental results show that ①the average hydrodynamic radius R h of the coils delermined by DLS decreases initially and then increases when the original salt concentration (OSC) in LPS increases: R h decreases rapidly from 450 to 250 nm while OSC increases from 0.5 to 2 g/L, to minimum 160 nm while OSC reaches 20 g/L and slightly increases with OSC further increasing; the R h values determined by SEM are in accordance with that by DLS and account 450 and 250 nm for the OSC equal to 0.5 and 2.0 g/L, respectively. ② varying salt concentration after LPS being formed influences R h value of coils in less extent; when the salt concentration increases from original value 0.5 to 2.0 g/L after crosslinking completed, the R h value decreases from 450 to 359 nm, a value higher than that in LPS of OSC=2 g/L(246 nm); when the salt concentration decreases from original value 2 to 0.5 g/L after crosslinking completed, the R h value increases from 246 to 326 nm, a value lower than that in LPS of OSC=0.5 g/L(450 nm). The changes in R h values determined with changing salt concentration are explained in terms of the change in hydration layer thickness caused by change in salt concentration and coil contraction/expansion. From these experimental phenomena it is concluded that there exists no phase interface between dispersed particles and dispersing media in LPS, water can freely flow out and into the hydrated coils and the coils in LPS are highly deformable.

关 键 词：交联聚合物溶液 聚合物分子线团 分子内交联 线团尺寸 水力学半径 NaCl 聚丙烯酰胺 柠檬酸铝 水体系 胶态分散凝胶 油田化学剂 盐浓度 

分 类 号：TE39[石油与天然气工程—油气田开发工程] TE357.46