Maleic anhydride grafts, which differ from physical blending and toughening in that they contain both polar aldehyde groups and non-polar olefin segments, can be chemically bonded to fillers and polymers to increase strength and toughness. There are numerous potential applications for the ideal mix.

Übersicht

A polymer called maleic anhydride graft is created by grafting maleic anhydride with other substances at the proper temperature. In general, the most common grafting techniques are the solution, melting, radiation, and solid phase procedures. The melting process is the most popular and significant of these. Maleic anhydride grafts can be used extensively in the modification of materials such as PA, PP and PE, wire and cable masterbatch, wood, and other olefin non-polar segments due to the polar group aldehyde group and polar segment given by maleic anhydride. It mostly performs the role of coupling compatibility in the plastics business, TPE encapsulation industry, and hot melt adhesive industry. the basis for action Under the influence of high temperature and screw shear, the anhydride group in the maleic anhydride graft can undergo a generalized dehydration reaction with the polar group (-NH2, -OH) and establish a chemical bond, turning the incompatible Chemical bonds link polar and non-polar molecules. Consider PA that has been graft-toughened using maleic anhydride. While olefins have strong processing and low-temperature toughness, PA has high mechanical qualities but poor low-temperature toughness. But because olefin is a non-polar polymer and PA is a polar polymer, compatibility between the two is challenging. Currently, the combination of the two can be successfully accomplished if maleic anhydride graft is employed (the reaction principle is depicted in Figure 1). Grafts made of maleic anhydride function similarly in various applications.  

Evaluation of superior maleic anhydride grafts

The following important aspects must be taken into account when evaluating high-quality maleic anhydride grafts: odor, grafting rate, yellowing index, and if ungrafted maleic anhydride is separated in the later stages of the reaction.It should be noted that because a large portion of the additional maleic anhydride is not grafted to the main chain, the grafting rate in the grafting reaction is often low. In the reaction system, polymaleic anhydride makes up the majority of the ungrafted maleic anhydride. The final result will therefore consist of a mixture of the graft and polymaleic anhydride if the product of the grafting process is not separated. In other words, there is a significant difference between the maleic anhydride grafting rate assessed before and after separation. The physical characteristics of high-quality maleic anhydride grafts often include low odor irritant, high grafting rate, and low yellowing index. High grafting rate, low yellowing index, low odor, and outstanding batch stability are all properties of Coace’s grafting products. They can be utilized in fields like hot melt adhesives, TPE, and multi-layer film co-extrusion, as well as the modification of materials like PA, PP, and PE, wire and cable masterbatch, wood plastic, etc. Among them, W1T grade and B1-2 grade are made of ethylene copolymer (-MAH), which has excellent weather resistance, antioxidant, and thermal stability properties. It can also reduce humidity sensitivity, improve dimensional stability, and improve the stability of materials made with glass fiber reinforced. influence performance. While the latter’s ethylene copolymer has high flow and amorphous characteristics, the former’s ethylene copolymer has medium viscosity and semi-crystalline characteristics, excellent room and low temperature toughness, and can improve the impact properties of polyamide at -20°C. At -40°C, impact performance.   A PP grafted homopolymer is B1R grade. Its primary element is PP-G-MAH. It is extremely fluid, highly impact resistant, and easily formable. Additionally, it has a high rate of grafting and significantly boosts PP and coupling in glass fibers, particularly those treated with aminosilane. A high-density polyethylene graft called W1H grade contains HDPE-MAH as its major constituent. It is extremely impact-resistant, highly adhesive, and moisture-resistant. These products frequently display various energy efficiencies in various specific applications; therefore, they must be tested using real applications.

Schlussfolgerung

Maleic anhydride grafts can be used in smaller amounts when altering materials like PA, PP, and PE compared to physical blending and toughening methods like POE. The best balance of strength and toughness is achieved by their chemical connection. By including maleic anhydride grafts, polar fillers and polymers can be coupled in the wood-plastic and flame-resistant wire and cable masterbatch industries. Maleic anhydride grafts can also be widely employed in industries like encapsulated TPE, hot melt adhesives, and multi-layer film co-extrusion because of their outstanding adsorption and adherence to polar substances.