两种聚酰胺-胺长链烷基季铵盐的合成和黏土稳定性能

Synthesis and Clay Stabilizing Ability of Poly(amidoamine) Quarternary Ammonium Salts with Long Chain Alkyl Groups

采用一步法合成了以乙二胺为核的端胺基树枝状聚合物PAMAM,再用正十二烷基溴和正十六烷基溴对端胺基进行季铵化,得到了两种大分子聚季铵盐PAMAMC12和PAMAMC16。用GPC方法测定,PAMAM的Mw和Mn分别为2237和1679,相对分子质量分布较窄,相当于2.2代PAMAM;用IR和1H NMR方法证实了中间产物和目标产物的分子结构,表明季铵化彻底。黏土膨胀测试结果表明,两种季铵盐稳定黏土的能力好于Mw=5000的一种PDMDAAC,而PAMAMC12又好于PAMAMC16,最佳浓度范围在2.0%-3.0%。在2%黏土稳定剂驱替低渗地层岩心实验中,注入10 PV PDMDAAC使渗透率下降65.7%,注入两种季铵盐时渗透率略有升高后缓慢下降,注入50PVPAMAMC12时略低于初始渗透率。低渗人造岩心注入5 PV季铵盐后渗透率不同程度上升,注入50 PV蒸馏水后仍高于初始值。PAMAMC12是可用于特低渗地层的优良黏土稳定剂。

An amine terminated poly（amidoamine） dendrimer PAMAM with ethylenediamine core was synthesized by one-step polymerization and was ammoniated with n-dodecyl and n-cetyl bromides to give two macromolecular polyammonium salts,PAMAMC12 and PAMAMC16.The Mw and Mn values of the PAMAM were determined by GPC as 2237 and 1679,respectively,which indicated a relatively narrow molar mass distribution and a generation 2.2.The chemical structures of the intermediate and the target products were identified and the completeness of ammoniation was ascertained by IR and 1H NMR spectra.The results of clay swelling tests showed that the clay stabilizing ability of the two polyammonium salts were stronger than that of a PDADMAC of Mw=5000 while PAMAMC12 is better than PAMAMC16 and the optimal solution concentration was in range 2—3%.In low permeable reservoir core flooding experiments with 2% clay stabilizer solution,10 PV of PDADMAC injected caused dramatical decrease in core permeability by 65.7%,injecting two polyammonium salts led to a slight increase followed by a slow decrease in core permeability,which was a little lower than the initial values when 50 PV of PAMAMC12 injected.The permeability of artificial low permeable cores flooded was raised in different extent when 5 PV of the two polyammonium salts solution injected and kept higher than initial values when 50 PV of distilled water injected.PAMAMC12 is an excellent clay stabilizer for ultralow permeable reservoirs.