兩性水膠的合成與對水泥砂漿試體水分散失的影響

Abstract

本研究合成兩性離子水膠PAMD與半交互穿插網狀結構水膠PAsp/PAM。PAMD是由丙烯酸二甲胺乙脂與氯醋酸鈉合成出DAAE單體，接著由丙烯醯胺與DAAE以自由基聚合的方式反應得到。PAsp/PAM是由天冬氨酸與磷酸反應得PSI，經水解後得PAsp，再由丙烯醯胺與PAsp反應得到。探討改變交聯劑、起始劑、單體比例、水解時間後在對水膠吸水率的影響。並將合成之PAMD與PAsp/PAM加入水泥砂漿試體中探討添加水膠對試體保水率、濕度、抗壓強度的影響。 研究結果顯示PAMD最佳反應條件為DAAE : AAm = 1 : 1、APS = 0.8 mol%、MBA = 0.5 mol%，所製得之PAMD在純水中的吸水率可達396 g/g；在 0.1M NaCl、0.1M CaCl2的吸水率分別為42 g/g、31 g/g，最佳水解時間為6小時，可使PAMD吸水率增加至473 g/g，在0.1M NaCl的吸水率增加至81 g/g。PAsp/PAM最佳反應條件為PAsp : AM = 1 : 1、APS = 0.8 mol%、MBA = 0.5 mol%，所製得之PAsp/PAM在純水中的吸水率可達92 g/g，在0.1M NaCl、0.1M CaCl2的吸水率分別為40 g/g、26 g/g，最佳水解時間為6小時，可使PAsp/PAM吸水率增加至405 g/g，在0.1M NaCl的吸水率增加至85 g/g。 測試結果可知添加0.1%的PAMD及0.2%的PAsp/PAM於水泥砂漿試體為最佳添加量，試體的保水率、內部相對濕度濕度、抗壓強度皆有略微提升。

In this research, two kind of hydrogel, i.e., zwitterionic hydrogel PAMD and semi-interpenetrating polymer network hydrogel PAsp/PAM, have been synthesized. First, DAAE was prepared from 2-(Dimethylamino) ethyl acrylate and sodium chloroacetate. Secondly, PAMD was prepared from Acrylamide and DAAE by free-radical polymerization. PSI was prepared from aspartic acid and phosphoric acid, PAsp was prepared from PSI by hydrolysis, PAsp/PAM was prepared from Acrylamide and PAsp. The effect of MBA, APS, monomer ratio and hydrolysis time on the swelling ratio of hydrogel were investigated. The effect of hydrogel in cement paste on the water retention, humidity and compressive strength was studied. The results indicate that the maximum water absorbency of PAMD(DAAE : AM = 1 : 1；APS = 0.8 mol%；MBA = 0.5 mol%)is 396 g/g in deionized water and 42 g/g, 31 g/g in 0.1M NaCl, 0.1M CaCl2 solution. The optimum hydrolyzed time is 6 hr, it can improve the water absorbency of PAMD 473 g/g in deionized water and 81 g/g in 0.1M NaCl solution. The maximum water absorbency of PAsp/PAM(PAsp : AM = 1 : 1；APS = 0.8 mol%；MBA = 0.5 mol%)is 92 g/g in deionized water and 40 g/g, 26 g/g in 0.1M NaCl, 0.1M CaCl2 solution. The optimum hydrolyzed time is 6 hr, it can improve the water absorbency of PAsp/PAM 405 g/g in deionized water and 85 g/g in 0.1M NaCl solution. The test on mortar containing 0.1% PAMD and 0.2% PAsp/PAM showed that the water retention, relative humidity and compressive strength were slightly higher than the control.