Maleated Coupling Agents for Wood Plastic Composites & Other Plastic Additives

UMEX - Acid Modified Polyolefin Coupling Agents

UMEX- Acid Modified Polyolefin Coupling Agents

Maleic-acid-modified low-molecular-weight polypropylene coupling agents. UMEX is superior to competitive products due to higher acid numbers which provide greater performance and allow lower addition levels. Benefits include improved bonding to reinforcing fibers and fillers, compatibilization of polymer blends, improved filler dispersion and enhanced adhesion. Recently developed grades offer lower melting points.

UMEX products are coupling agents based on modified low molecular weight polypropylene containing pendant maleic anhydride groups. The non-polar polypropylene backbone provides affinity for polyolefin resins while the hydrophilic carboxylic anhydride groups provide affinity for reinforcing fillers such as glass fiber, carbon fiber and wood flour.  This structure also serves to compatibilize blends of polyolefins with high-polarity resins such as nylon and PET.  Our unique technology permits a higher degree of acid modification than conventional  maleated coupling agents.  An advantage of the high acid-number UMEX products is that they can be used at lower loadings than conventional products, thus yielding cost savings

UMEX Maleated Coupling Agent Applications

Glass Fiber Reinforced Polypropylene

One of the applications currently benefiting from high acid-number UMEX products is glass fiber reinforced polypropylene. The purpose of adding a reinforcing filler to polyolefin resin is to improve the physical properties and heat resistance of the resin. High acid-number UMEX can be used at lower loadings than conventional products, thus yielding cost savings.  Additional information is contained in our whitepaper.

Polypropylene/Nylon-6 Blend Compatibilization with UMEX

Another popular application is carbon fiber reinforced polypropylene, which fulfills the promise of “stronger than steel and lighter than aluminum” performance. This material is desirable for demanding automotive applications in which weight reduction is key to achieving fuel economy targets. Additional information is contained in our whitepaper.

UMEX IN Wood Plastic Composite

Another application is WPC (Wood Plastic Composite).  This is a composite of wood flour (powdered wood) and a synthetic resin. It’s used mainly for residential decks and outdoor structures. It looks and feels like wood but offers better strength, dimensional stability, weather resistance, flame resistance, chemical resistance and abrasion resistance than wood. What’s more, we have developed special “low melting point” UMEX grades which allow lower processing temperatures. This is important for WPC, due to the temperature sensitivity of cellulose fillers. Additional information is contained in our whitepaper.

Polymer Alloys

Perhaps the most exciting application is that of “polymer alloys”. Polyolefins are non-polar and crystalline, so they tend to have poor compatibility with other polymers and, thus, generally make poor polymer alloys. UMEX is based on a polyolefin backbone with bonded pendant maleic anhydride groups. When preparing a polymer alloy of polyolefin resin and nylon, UMEX is a useful compatibilizer. The maleic anhydride groups from UMEX and the amino end groups and amide linkages of the nylon react, resulting in a reduction of interfacial tension between the resins, leading to a state of micro-dispersion. UMEX is available for use with not only nylon but also other high polarity resins such as PET to improve their compatibility with polypropylene resins. Additional information is contained in our whitepaper.

UMEX Grade Line-Up

FAQs About Maleated Coupling Agents and Other Plastic Additives

A coupling agent is used to create a strong bond between two surfaces. This can be between glass fiber and polyolefin or between wood flour and polyolefin.

A coupling agent can also create a bond between two immiscible polymers in a polymer alloy.

A maleated coupling agent is a coupling agent made from the reaction of maleaic acid and functionalized polypropylene.

Maleic acid has proven to be useful in the creation of strong bonds between dissimilar materials.

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