反应型相容剂是一种同非极性高分子主链Pc及活性基团(如羟基、环氧基组成，多为无规的)组成的聚合物。由于它的非极性高分子主体能与共混物中的非极性聚合物相容，而极性基团又能与共混物的极性聚合物的活性基团反应或键合，故能起到很好的相容作用。其作用示意图 如下:
Reactive compatibilizer is a kind of polymer composed of non-polar polymer main chain Pc and active groups (such as hydroxyl, epoxy, mostly random). Because its non-polar polymer can be compatible with the non-polar polymer in the blend, and the polar group can react or bond with the active group of the polar polymer in the blend, it can play a good compatibility role. The schematic diagram of its function is as follows:
一般是大分子型的，其活性官能团可以在分子的末端，也可以在分子的侧链上，其大分子主链可以和共混体系中的至少一种高分子基体相同，也可以不同，但在不同的情况下，其大分子主链应和共混体系中的至少一种高分子基体有较好的相容性。
Generally speaking, the active functional group can be at the end of the molecule or at the side chain of the molecule. The main chain of the macromolecule can be the same as or different from at least one polymer matrix in the blending system. However, in different circumstances, the main chain of the macromolecule should be at least one polymer group in the blending system. The body has good compatibility.
(1)环状酸酐型(MAH)。环状酸酐型类反应型相容剂是目前最常用的一类反应型相容剂。其中，以马来酸酐接枝到聚烯烃上的马来酸酐相容剂为主，其接枝率一般为0.8%-1.0%，主要应用于聚烯烃塑料的改性。将马来酸酐接枝到PS或以PS为基体的二元或多元共聚反应型相容剂，可应用于PA/PC、ABS/GF、PA/ABS的改性、共混或合金。一般用量5%-8%。
(1) Cyclic anhydride type (MAH). Cyclic anhydride type reactive compatibilizer is the most commonly used type of reactive compatibilizer at present. Among them, maleic anhydride is the main compatibilizer grafted onto polyolefin, and its grafting rate is generally 0.8% - 1.0%. It is mainly used in the modification of polyolefin plastics. Binary or multicomponent copolymerization compatibilizers grafting maleic anhydride onto PS or PS matrix can be used for modification, blending or alloying of PA/PC, ABS/GF, PA/ABS. The general dosage is 5%-8%.