陽性離子交換樹脂是由酚苯基乙烯或酚的同系物和醛的衍生物疊合或聚合的產物或其他類似有複雜結構的化合物如磺化煤等由於經過特殊的處理,在它們的組成中產生有活性的酸基-SO_3H,-COOH,酚基-OH等。這些活性基因為和樹脂的主體結構相連,它們不能轉移到溶液中;但這些活性基中的氫離子或取代了H~+的阳離子是可以運動的。離子交換的 Positive ion-exchange resins are products that are superposed or polymerized from phenolic phenyl ethylene or homologs of phenols and derivatives of aldehydes or other compounds with complex structures such as sulfonated coals, etc. because of special treatment in their composition The active acid groups -SO3H, -COOH, phenol-OH etc. are produced. These active genes are linked to the main structure of the resin and they cannot be transferred to the solution; however, the hydrogen ions in these active groups or the cations that replace H+ are mobile. Ion exchange