Polyolefin Modification Technology: Preparation, Principle And Application of Maleic Anhydride Grafted Polyolefin

Polyolefin Modification Technology: Preparation, Principle And Application of Maleic Anhydride Grafted Polyolefin

Polyolefin (PO, polyolefin) is a general-purpose plastic with excellent comprehensive performance, widely used in automotive, electrical appliances, packaging and other fields. However, since polyolefin is a non-polar polymer, it is incompatible with polar polymers (nylon, polylactic acid, etc.) and polar fillers (glass fiber, carbon fiber, etc.). Maleic anhydride grafted polyolefin is a commonly used compatibilizer for the production of modified polyolefin products, and can be prepared separately as a compatibilizer masterbatch for downstream production of modified polyolefin plastic materials.

What is maleic anhydride grafted polyolefin?

Maleic anhydride grafted polyolefin masterbatch conventional production method for melt grafting process. The reaction principle is to add polyolefin resin, maleic anhydride, free radical initiator, antioxidant and so on to the twin-screw extruder, through the front section of the twin-screw rotating shear effect and heating device heating effect, the resin will be melted and plasticized and will be dispersed by the additives; in the middle and latter part of the screw will be all the materials melted and homogenized grafting, and finally extrusion pelleting, to get the maleic anhydride grafted polyolefin masterbatch products.

Categorization

Maleic anhydride grafted compatibilizers are mainly as follows:

1. Maleic anhydride grafted ABS (ABS-g-MAH)

2. Maleic anhydride grafted PE (PE-g-MAH)

3. Maleic anhydride grafted PP (PP-g-MAH)

4. Maleic anhydride grafted PS(SMA)

5. Maleic anhydride grafted POE (POE-G-MAH)

6. maleic anhydride grafted EVA(EVA-G-MAH)

Principle

The chemical reaction principle mainly includes the following aspects:

(1) Free radical initiated grafting: In the grafting process, organic peroxides are usually used as initiators, which decompose under high temperature conditions to produce free radicals. These free radicals are able to attack the hydrocarbon chain of polyolefin and form polyolefin radicals. Polyolefin radicals further react with maleic anhydride monomers to form graft copolymers.

(2) Reactivity of the anhydride group: The maleic anhydride group (-CO-O-CO-) of maleic anhydride is able to react with the polar groups in the polyolefin (e.g., -NH2, -OH) in a dehydrating reaction to form a chemical bond at high temperatures and under the action of screw shear. This chemical bonding enables incompatible polar and non-polar substances to be chemically coupled.

(3) Complexity of grafting reaction: the reaction mechanism of polyolefin grafting maleic anhydride is complicated and accompanied by side reactions, such as cross-linking of polyethylene and degradation of polypropylene. In order to inhibit these side reactions, some electron donor compounds containing N, P, S atoms can be added, such as dimethylformamide (DMF), dimethylacetamide (DMAC).

(4) Influential factors: factors affecting the reaction of polyolefin grafted maleic anhydride include initiator species and concentration, monomer mass concentration, additive species and concentration, reaction temperature and reaction time. For example, an increase in the concentration of the initiator DCP (diisopropyl peroxide) can improve the grafting rate, but excessive DCP will lead to cross-linking reactions.

(5) Relationship between grafting rate and performance: factors such as grafting rate, grafting position and structure closely affect the performance of the grafted product, so it is very important to characterize the graft. Determination of grafting rate can be carried out by methods such as chemical titration and infrared spectroscopy.

Application

1. Enhanced compatibility: Maleic anhydride grafted polyolefins have polar groups that can form chemical bonds with non-polar polyolefin chain segments, thus improving compatibility between different polymers. This makes them widely used in plastic modification, especially in the alloying of polyolefins with other polymers (e.g. polyamide PA, polycarbonate PC, etc.).

2. Improve physical properties: grafted polyolefin shows a good balance of strength and toughness, and is suitable for the manufacture of packaging films, pipe bonding materials and wire and cable masterbatch.

3. As coupling agent: maleic anhydride grafted polyolefin can also be used as a coupling agent between the filler and the polymer, to improve the bonding effect between the polymer and the filler, to enhance the performance of the composite material.

4. Application to engineering plastics: In the modification of engineering plastics, maleic anhydride grafted polyolefin can effectively improve the processability and performance of the material, which is widely used in the field of wood-plastic composites, masterbatch carrier resins and so on. Through these applications, maleic anhydride grafted polyolefin plays an important role in the plastics industry, promoting the enhancement and diversification of material properties.

With the continuous development of the plastics industry, the requirements for material properties are increasing. Maleic anhydride grafted polyolefin, as one of the key technologies for modified polyolefin products, has demonstrated its unique value in many fields, and YINSU Flame Retardant Company, following the trend of the industry, has researched and developed flame retardants, some of which are also pelletized with maleic anhydride grafting technology, which not only improves the performance of the flame retardants, but also further broadens the scope of their applications.

Through the application of this innovative technology, YINSU Flame Retardant Company's products not only improve the flame retardant properties of the materials, but also ensure the other physical properties of the materials, contributing to the sustainable development of the plastics industry. In the future, we will continue to promote the overall improvement of plastic material performance through technological innovation, and provide safer and more efficient material flame retardant solutions for the development of various industries.