A temperature-sensitive polymer—hydroxyl isopropoxy triethyl ammonium chloride cellulose ether—was prepared from hydroxypropyl methyl cellulose (HPMC) and with epoxypropyl triethyl ammonium chloride as the hydrophobization reagent. Then, the reaction conditions of etherification reaction time, mass ratio of the etherifying agent to HPMC, molar ratio of alkali to etherifying agent, and concentration of HPMC were optimized. The structures of the products were characterized via nuclear magnetic resonance and infrared spectrum, and the temperature sensitivity was analyzed via ultraviolet spectrophotometry. It was found that the degree of substitution significantly affected the temperature sensitivity and lowest inversion temperature of the hydroxyl isopropoxy triethyl ammonium chloride cellulose ether. The effects of the substitution degree rising from 0.19 to 0.50 on the water retention value were explored. When the molar ratio of alkali to HPMC was constant, the water retention value declined with the increased substitution degree of cationic cellulose ether. The temperature rise of phase transformation in this process was fully reversible and nonhysteretic. Since the polymer variation originated from the change of intramolecular and intermolecular forces during the heating process, here the effects of addictive micromolecules on the regulator solution were further studied. As the NaOH concentration rose, the substitution degree and water retention value both first increased and then declined and both maximized at the NaOH concentration of 20.7%. Graphical abstract

中文翻译：

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一种新型温敏阳离子疏水纤维素醚：制备与表征

以羟丙基甲基纤维素（HPMC）为原料，以环氧丙基三乙基氯化铵为疏水剂，制备了一种温度敏感聚合物——羟基异丙氧基三乙基氯化铵纤维素醚。然后对醚化反应时间、醚化剂与HPMC的质量比、碱与醚化剂的摩尔比、HPMC的浓度等反应条件进行了优化。通过核磁共振和红外光谱对产物的结构进行表征，并通过紫外分光光度法分析其温度敏感性。发现取代度显着影响羟基异丙氧基三乙基氯化铵纤维素醚的温度敏感性和最低转化温度。探讨了取代度从0.19上升到0.50对保水值的影响。当碱与HPMC的摩尔比一定时，随着阳离子纤维素醚取代度的增加，保水值下降。该过程中相变的温升是完全可逆的和非滞后的。由于聚合物的变化源于加热过程中分子内和分子间力的变化，这里进一步研究了成瘾性小分子对调节剂溶液的影响。随着NaOH浓度的升高，取代度和保水值均先升高后下降，均在NaOH浓度为20.7%时达到最大值。图形概要 当碱与HPMC的摩尔比一定时，随着阳离子纤维素醚取代度的增加，保水值下降。该过程中相变的温升是完全可逆的和非滞后的。由于聚合物的变化源于加热过程中分子内和分子间力的变化，这里进一步研究了成瘾性小分子对调节剂溶液的影响。随着NaOH浓度的升高，取代度和保水值均先升高后下降，均在NaOH浓度为20.7%时达到最大值。图形概要 当碱与HPMC的摩尔比一定时，随着阳离子纤维素醚取代度的增加，保水值下降。该过程中相变的温升是完全可逆的和非滞后的。由于聚合物的变化源于加热过程中分子内和分子间力的变化，这里进一步研究了成瘾性小分子对调节剂溶液的影响。随着NaOH浓度的升高，取代度和保水值均先升高后下降，均在NaOH浓度为20.7%时达到最大值。图形概要 该过程中相变的温升是完全可逆的和非滞后的。由于聚合物的变化源于加热过程中分子内和分子间力的变化，这里进一步研究了成瘾性小分子对调节剂溶液的影响。随着NaOH浓度的升高，取代度和保水值均先升高后下降，均在NaOH浓度为20.7%时达到最大值。图形概要 该过程中相变的温升是完全可逆的和非滞后的。由于聚合物的变化源于加热过程中分子内和分子间力的变化，这里进一步研究了成瘾性小分子对调节剂溶液的影响。随着NaOH浓度的升高，取代度和保水值均先升高后下降，均在NaOH浓度为20.7%时达到最大值。图形概要 在NaOH浓度为20.7%时，取代度和保水值均先升高后降低，均达到最大值。图形概要 在NaOH浓度为20.7%时，取代度和保水值均先升高后降低，均达到最大值。图形概要