<br><div><section class="_135editor" data-role="paragraph" style="font-size: medium; max-inline-size: 100%; margin: 0px; padding: 0px; border: 0px none; z-index: 0; overflow-wrap: break-word !important; outline: none 0px !important;"><p style="max-inline-size: 100%; margin-bottom: 0px; clear: both; min-height: 1em; cursor: text; line-height: 1.75em; overflow-wrap: break-word !important; outline: none 0px !important;"><span style="max-inline-size: 100%; margin: 0px; padding: 0px; cursor: text; font-size: 15px; overflow-wrap: break-word !important; outline: none 0px !important;">　　答 在阴离子型表面活性剂中加入与表面活性剂离子相反的电解质，一般可提高表面活性，降低临界胶束浓度(CMC)。因为增加离子型表面活性剂的反离子浓度，影响表面活性剂胶束的扩散双电层，减少表面活性离子之间的排斥作用，而使双电层厚度缩小，从而使胶束容易形成，使表面张力下降，CMC降低。例如：在C12H25·OSO3Na溶液中，增加NaCl浓度，如加入0．02mol／L浓度时，可使CMC由原来的0．0081mol／L降至0．0038mol／L，加入浓度为0．2mol／L，CMC降至0．00083mol／L，同时在液体洗涤剂中加入少量的食盐(NaCl)还可提高洗涤剂的浓度，但用量不能过多，否则易产生沉淀。一般液状洗涤剂可加入NaCl 1％左右，粉状洗涤剂可加入Na2SO4 20％～40％。</span></p><p style="max-inline-size: 100%; margin-bottom: 0px; clear: both; min-height: 1em; cursor: text; overflow-wrap: break-word !important; outline: none 0px !important;"><br style="max-inline-size: 100%; margin: 0px; padding: 0px; overflow-wrap: break-word !important; outline: none 0px !important;"></p><p style="max-inline-size: 100%; margin-bottom: 0px; clear: both; min-height: 1em; cursor: text; line-height: 1.75em; overflow-wrap: break-word !important; outline: none 0px !important;"><span style="max-inline-size: 100%; margin: 0px; padding: 0px; cursor: text; font-size: 15px; overflow-wrap: break-word !important; outline: none 0px !important;">　　电解质对非离子型表面活性剂的影响较小，但电解质加到溶液中以后，可使非离子型表面活性剂的浊点降低，这就是电解质的“盐析’,作用。“盐析”作用使非离子型表面活性剂聚集成更大的胶束，到一定程度即分离出新相。如果该洗涤剂是阴离子型表面活性剂与非离子型表面活性剂的拼混物，则加入NaCl后，一方面非离子型表面活性剂加入阴离子表面活性剂可使浊点提高；一方面又能使浊点降低。在这种情况下还是不加NaCl为好。</span></p><p style="max-inline-size: 100%; margin-bottom: 0px; clear: both; min-height: 1em; cursor: text; overflow-wrap: break-word !important; outline: none 0px !important;"><br style="max-inline-size: 100%; margin: 0px; padding: 0px; overflow-wrap: break-word !important; outline: none 0px !important;"></p></section><section class="_135editor" data-role="paragraph" id="autoparagraph" style="font-size: medium; max-inline-size: 100%; margin: 0px; padding: 0px; border: 0px none; z-index: 0; overflow-wrap: break-word !important; outline: none 0px !important;"><p style="max-inline-size: 100%; margin-bottom: 0px; clear: both; min-height: 1em; cursor: text; overflow-wrap: break-word !important; outline: none 0px !important;"><br style="max-inline-size: 100%; margin: 0px; padding: 0px; font-family: 微软雅黑, &quot;Microsoft YaHei&quot;, sans-serif; font-size: 17px; caret-color: rgb(255, 0, 0); overflow-wrap: break-word !important; outline: none 0px !important;"></p></section></div>