3W worth of additives quick reference manual, modified plastics R & D engineers must!
No single thing in the world is perfect, and in the modified plastics industry, such examples are even more common. In the modified plastics industry, such cases are even more common, because, whether thermoplastic or thermoset, there will always be some plastics that are not satisfactory during processing and molding or use, despite the careful selection of materials. For this reason, in order to meet the requirements of the processing and molding or use process, it is necessary to modify the plastic.
Because, some materials are very good toughness, but the flame retardant performance is very poor; some materials are very good electrical conductivity, heat resistance is very poor; some materials have good overall performance, aging resistance and yellowing resistance performance is not. This time, modified plastics people’s most effective savior is – “plastic additives”. Additives in plastics: small body, big energy.
Plastic additives, also known as plastic additives, is a polymer (synthetic resin) for molding and processing to improve its processing properties or to improve the performance of the resin itself is insufficient and must be added to some compounds.
A. What can additives do?
What can additives do? I think people who do plastic modification are very clear. For example: improve processing properties, improve mechanical properties, improve optical properties, improve aging properties, improve surface properties, reduce costs and improve some other properties. Here is a table to get an overall feeling.
Table Plastic additives function and category
Improve processing performance
Lubricants, mold release agents, stabilizers, processing aids, thixotropic agents, plasticizers, PVC stabilizers
Improving mechanical properties
Plasticizers, reinforcing fillers, toughening agents, impact modifiers
Improvement of optical properties
Pigments, dyes, nucleating agents, fluorescent brighteners
Improving aging properties
Antioxidants, PVC stabilizers, UV absorbers, fungicides, mildew inhibitors
Improving surface properties
Antistatic agents, slip agents, abrasion inhibitors, anti-stick agents, anti-fogging agents
Cost reduction
Thinner, solubilizer, filler
Improvement of other properties
Foaming agents, accelerators, chemical cross-linking agents, coupling agents
Although it is said that additives can improve some properties of plastics, not every kind of plastic can be added with different additives. This is mainly because some additives will have some reactions with the plastic itself, which not only fail to achieve the problem of improving the plastic’s own shortcomings, but also make the material performance worse and cause immeasurable impact on human health, environment, etc. Therefore, today we will come together from the overall out, one by one to understand the various plastic additives, so as to improve the understanding of the performance of plastics.
Second, the introduction of additives
1. Flame retardants
Flame retardants, functional additives that give flammable polymers flame-retardant, mainly designed for flame retardant polymer materials; there are various types of flame retardants, which are divided into additive flame retardants and reactive flame retardants according to the method of use.
As the country pays more and more attention to environmental protection, the development trend of flame retardants will be non-toxic, halogen-free, low-smoke, the impact on the environment with the best flame retardant performance of the new flame retardant system.
Classification of flame retardants and classical introduction
2. Anti-oxidants / light stabilizers
Antioxidants are a class of chemicals that, when present in only small amounts in polymer systems, can delay or inhibit the oxidation process of polymers, thus preventing the aging of polymers and extending their service life, also known as “antioxidants”. Pictures
Different types of primary and secondary antioxidants, or the same type of antioxidants with different molecular structures, the function and application of the effect of differences, commonly used plastic antioxidants according to the molecular structure and mechanism of action are generally divided into five categories: hindered phenols, phosphite, thio, compound and hindered amine (HALS) class.
3. Smoothing agent
Polymers can cause problems such as surface bonding and release difficulties in production and processing due to their frictional nature. High friction in the film winding, plastic bag production and packaging production process to create difficulties. Therefore, in the polymer production process need to add some slip additives to reduce friction or bonding.
4. Compatibility agent
Compatibility agents, also known as capacitors, are additives that promote the combination of two incompatible polymers with the help of intermolecular bonding forces, thereby obtaining a stable blend.
Take ABS for example, directly blending two materials to get “ABS” must not be what you want, because its performance is a mess. Why is there such a difference? This brings us to the key technology of polymer alloys – compatibility technology. In the case of ABS, you may know that it is produced by first polymerizing the PB powder and then using it as a seed to add acrylonitrile and styrene monomers to graft on the PB powder. In this way, the surface of the PB powder is actually a PB-g-AS polymer. And this polymer combines two originally incompatible polymers together, improving the performance of the original system.
5. Toughening agent
Where can reduce the brittleness, increase the toughness, and does not affect the other main properties of the adhesive substances that are toughening agents, can be divided into rubber toughening agents and thermoplastic elastomer toughening agents. Toughening agents generally contain reactive groups, chemical reaction with the resin, after curing is not fully compatible, and sometimes also divided into phases, will obtain a more desirable toughening effect, so that the heat deflection temperature remains unchanged or decreased very little, while the impact resistance is significantly improved.
Thermoplastic elastomer
6. Antibacterial agent
Antimicrobial agents (anti-bacterial agents) refer to chemical substances that can keep the growth or reproduction of certain microorganisms (bacteria, fungi, yeast, algae and viruses, etc.) below the necessary level for a certain period of time. Anti-bacterial agents are substances or products with antibacterial and bactericidal properties.
Silver ion antibacterial mechanism
The antimicrobial effect of antimicrobial agents is generally divided into bactericidal and bacteriostatic effects. The concentration and duration of action of the antimicrobial agent have a great influence on the antimicrobial effect. Silver, copper, mercury and other metal ions, strong oxidizing agents mainly play a bactericidal role, organic antimicrobial agents are mainly shown to inhibit the role of bacteria. The same antimicrobial agent, low concentration often shows inhibition, high concentration is bactericidal.
7. Coloring agent
Can make the plastic on a certain color of the substance. Coloring agents make plastic change the inherent characteristics of absorbing and reflecting light waves. It can be organic or inorganic, can be natural or synthetic.
Pigments are colorants that are not soluble in common solvents, so to obtain the desired coloring properties, the pigments need to be dispersed uniformly in the plastic by mechanical means. Inorganic pigments have excellent heat stability and light stability, low price, but the coloring power is relatively poor and the relative density is large; organic pigments have high coloring power, bright color, complete chromatography and small relative density, but the disadvantage is that the heat resistance, weather resistance and covering power are not as good as inorganic pigments.
8. Coupling agent
They are a class of substances with amphoteric structure, part of their molecular groups can react with inorganic surface chemical groups to form chemical bonding; the other part of the group has the nature of pro-organic substances, which can chemically react with organic molecules or produce strong intermolecular effects, so as to firmly combine two materials with very different properties, improve the dispersion of inorganic fillers in the polymer matrix, and improve the filling The mechanical properties and performance of polymer materials.
Titanate coupling agent
For more information about coupling agents, please click on the blue link:
Coupling agents – the essential bonding agent for reinforced plastics
Polyscope Netherlands, the world’s leading SMA manufacturer, will launch new compatibilizers and coupling agents
9. Nucleating agents
Nucleating agent is suitable for polyethylene, polypropylene and other incomplete crystalline plastics, through changing the crystallization behavior of the resin, accelerate the crystallization rate, increase the crystallization density and promote the grain size microfabrication, to shorten the molding cycle, improve the transparency of the product, surface gloss, tensile strength, rigidity, heat deflection temperature, impact resistance, creep resistance and other physical and mechanical properties of functional additives.
Sorbitol-based nucleating agents
For more nucleating agent related knowledge, please click on the blue link:
Innovation knows no bounds, Meriken brings innovative additive solutions to Chinaplas 2016
Honeywell Nucleating Agent Solutions in Nylon
I am nucleating agent, this is my resume, please bookmark
10. Blowing agent
The so-called blowing agent is the substance that makes the object material into a hole, it can be divided into three categories: chemical blowing agents and physical blowing agents and surfactants. Chemical blowing agents are those that can release gases such as carbon dioxide and nitrogen after decomposition by heating, and the formation of fine pores in the composition of the polymer compounds; physical blowing agent is the foam fine pores are formed by a change in the physical form of a substance, that is, through the expansion of compressed gas, liquid volatilization or dissolution of solids; blowing agents all have a high surface activity, can effectively reduce the surface tension of the liquid, and in The surface of the liquid film double electron layer arrangement and surround the air, forming bubbles, and then from a single bubble composed of foam.
After foaming TPU material
For more knowledge related to foaming agents, you can click on the blue link at
The residual amount of AC blowing agent in shoe materials is limited, but can be used in food?
China broke the international monopoly first chemical synthesis of non-chlorofluorine polyurethane chemical blowing agent
Plastic foaming, do you know this?
How is the popular foamed polypropylene material produced in recent years?
11. Antistatic agent
Any object with its own electrostatic charge, this charge can be negative or positive charge, the gathering of electrostatic charge to life or industrial production is affected or even harm, the gathering of harmful charges to guide / eliminate so that it does not cause inconvenience or harm to production / life of chemicals called antistatic agents.
Antistatic
