Do you know several methods for modifying nylon?

1、 What is nylon?
Polyamide, commonly known as Nylon, is a general term for thermoplastic resins containing repeating amide groups - [NHCO] - on the main molecular chain, including aliphatic PA, aliphatic aromatic PA, and aromatic PA. Among them, there are many varieties of aliphatic PA, with a large yield and wide application. Its name is determined by the specific carbon atom number of the synthesized monomer. It was invented by American chemist Carothers and his research team.
2、 How is nylon used for modification?
Nylon has excellent mechanical properties, electrical properties, * *, and chemical resistance, but it also has a major drawback, which is its high water absorption, which can lead to dimensional instability of the product. If we modify nylon, it will mainly be modified from both physical and chemical aspects.
Chemical modification is mainly achieved by adding a second and third monomer to form copolymerized nylon. In terms of physical modification, we need to achieve the goal of modification through methods such as reinforcement, toughening, flame retardancy, filling, blending alloys, and nano modification.
1. Blended alloy modification
The main method is to form a continuous dispersed phase between nylon and other plastics, or to add compatibilizers to form a uniform and stable phase until there is no intermediate interface. This method is called "blending alloy". For example, if the film formed by the "layered co extrusion" of PE and PA6 has good barrier properties, then a co blend can also be used for modification.
In the modification of co mixed alloys, the key is to choose the appropriate compatibilizer. There are usually two types of "MAH and MMA" grafted compatibilizers on the market, and it is necessary to choose the appropriate graft for blending alloys (such as PA and PP, PA and PPS, PA and PC). Many times, we believe that two incompatible materials can also be made into alloys to improve their impact, rigidity, heat resistance, dimensional stability, and so on.
2. Toughening modification
When the following situations occur, we need to toughen nylon: synthetic resin itself has insufficient toughness, and toughness needs to be improved to meet usage needs, such as GPPS, homopolymer PP, etc; Alternatively, it may be necessary to significantly improve the toughness of plastics to meet the requirements of super toughening and long-term use in low-temperature environments, such as super tough nylon; The modification of the resin, such as filling and flame retardancy, has caused a decrease in the toughness of the material, and effective toughening is necessary at this time. Mainly by adding rubber components and utilizing the "silver grain shear theory", the toughness of the material is improved.

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3. Glass fiber reinforced modification
If nylon needs better heat resistance and rigidity to obtain better bending strength and Flexural modulus, it is a good method to use glass fiber for reinforcement and modification. It has many applications in automobiles, household appliances, and many electric tools.
So in the modification process, you can choose "alkali free glass fiber", which has relatively better electrical insulation. Then, add coupling agents and try to choose temperature resistant, non decomposing, and non volatile coupling agents. At the same time, adjust the screw combination to prevent the exposure of glass fibers or excessive temperature from causing the material to be burnt and affecting its physical properties.
4. Filled nylon modification
Calcium carbonate, talc, Wollastonite, kaolin and mica powder are used for modification. Except for calcium carbonate, all other structures are columnar, needle like, rod-shaped, layered, and other different structures, which can also play a reinforcing and anti warping role in nylon resin.
5. Nano modification
Utilize the surface effect, volume effect, and macroscopic quantum tunneling effect of nanoscale materials for modification. The performance of nanocomposites is usually superior to that of conventional composite materials, but one issue to be noted is that they are prone to agglomeration. Therefore, when conducting nano modification, it is necessary to solve the problem of agglomeration in order to obtain relatively excellent nanomaterials. Among them, it is good to use Graphene to achieve the effect of modification.