Types of compatibilizers and methods of selection

Non-reactive solubilizer

Non-reactive compatibilizers are currently relatively compatible compatibilizers. The method of compatibilizing by adding a non-reactive compatibilizer in an incompatible polymer system is the most common in polymer alloy technology. The non-reactive compatibilizer is generally a copolymer, and may be a block copolymer or a graft copolymer or a random copolymer.

Reactive compatibilizer

The reactive compatibilizer is a polymer composed of a non-polar polymer backbone Pc and a reactive group such as a hydroxyl group or an epoxy group, which are mostly random.

Low molecular type compatibilizer

Low molecular compatibilizers are reactive compatibilizers, compatible with reactive monomers and low molecular weight polymers, including one that can be synthesized with plastics, and reacted, crosslinked or bonded to another component. Thereby forming organic and inorganic compounds of plastic alloys.

Second, how to choose the right compatibilizer

The compatibilizer is a block copolymer obtained by copolymerization of monomers of two polymer blends, or a graft copolymer, or a functional group which chemically reacts with the blending component, and can be distributed in two or more kinds. The copolymer between the mixed polymer interfaces serves to reduce the interfacial tension, prevent the dispersed phase from agglomerating, and stabilize the formed phase morphology structure to increase the compatibility of two or more polymers.

The relative molecular mass of the compatibilizer should match the relative molecular mass of the corresponding blend and have good compatibility. In general, the compatibility of the diblock copolymer is superior to the compatibility of the triblock copolymer.

For example, PE/PP blends have low mechanical strength. If a PE/PP blend is added with 4% to 8% of PE and PP block copolymer (PE-b-PP) as a compatibilizer, The mechanical strength can be greatly improved.

Another example is SEBS, which can be used as a compatibilizer for PE/PS, PP/PS, PET/PE blends.