By adding the inorganic mineral (organic) powder to ordinary plastics, the rigidity, hardness and heat resistance of plastic materials are improved. There are many kinds of fillers, and their properties are complex.
The role of plastic fillers: improve the performance of plastic processing, improve the properties of materialization, increase volume, reduce costs.
Requirements for plastic additives:
(1) The chemical properties are inert and do not have adverse reactions with resins and other additives;
(2) does not affect the water-resistance of plastics, chemical resistance, weather resistance, heat resistance, etc.
(3) does not reduce the physical properties of plastics;
(4) can be filled in large quantities;
(5) density is relatively small, the density of products has little impact.
Reinforcement measures: by adding fiberglass, carbon fiber and other fibrous substances.
Enhanced effect: can significantly improve the rigidity, strength, hardness, heat resistance of the material,
Adverse effects of modification: However, many materials can lead to poor surfaces and reduced fracture elongation.
Enhanced principle:
(1) The reinforcing material has high strength and modulus;
(2) Resin has much inherent excellent physics, chemistry (corrosion- and insulation-resistant, irradiated, transient high-temperature ablation, etc.) and processing properties;
(3) After the resin and the reinforcing material are composited, the reinforced material can enhance the mechanics or other properties of the resin, while the resin can play the role of bonding and transferring loads to the reinforced material so that the enhanced plastic has excellent properties.
There are much material toughness is not enough, too brittle, can be added to better toughness materials or ultra-fine inorganic materials, increase material toughness and low-temperature performance.
Toughener: An additive added to the resin in order to reduce the brittleness of plastic hardening and improve its impact strength and elongation.
Common tougheners - mostly Malay antic acid graft compatibility agents:
Ethylene-vinyl acetate copolymer (EVA)
Polyolefin Elastomer (POE)
Polyethylene chloride (CPE)
Acrylonitrile-butadiene-styrene copolymer (ABS)
Styrene-butadiene thermoplastic elasticity (SBS)
3 yuan ethyl propylene rubber (EPDM)
Plastic modification by flame retardant (halogen-free flame retardant)
In electrical and electronic appliances, automobiles and many other industries require materials to have flame retardant, but many plastic raw materials themselves are low flame retardant. Increased flame retardants can be achieved by adding flame retardants.
Flame retardants: also known as refractory agents, flame refractors or fire extinguishing agents, which give flammable polymers refractory functional additives;
Anti-smoking compounds such as anti-smoking compounds, tin compounds and iron compounds are also in the category of flame retardants, mainly applicable to plastics with flame retardant needs, delay or prevent the burning of plastics, especially polymeric plastics. Make it ignite time to grow, ignite self-extinguishing, difficult to ignite.
Plastic flame retardant rating: increment from HB, V-2, V-1, V-0, 5VB to 5VA step by step.
Plastic modification by weather resistance (anti-aging, UV, low temperature)
Generally refers to the cold resistance of plastic at low temperature, because of the inherent low-temperature brittleness of plastic, so that plastic at low temperature is brittle, so for many plastic products used in a low-temperature environment, generally requires that it has cold resistance.
Weather resistance: refers to plastic products due to sunlight, temperature changes, wind and rain and other external conditions, and the appearance of fading, discoloration, cracking, powdering and intensity decline of a series of aging phenomena. Ultraviolet radiation is a key factor in the aging of plastics.
Plastic modification by alloy
Plastic alloy is the use of physical mixing or chemical grinding, co-polymerization method, two or more materials prepared into high-performance, functional, specialized a new material, to improve the performance of a material or both material characteristics. It improves or improves the performance of existing plastics and reduces costs.
General plastic alloys: such as PVC, PE, PP, PS alloys are widely used, production technology has been widely mastered.
Engineering plastic alloy: generally refers to the comix of engineering plastics (resins), including PC, PBT, PA, POM (polyformaldehyde), PPO, PTFE (polytetrafluoroethylene) and other engineering plastics as the main mixing system, as well as ABS resin-modified materials.
The growth rate of PC/ABS alloys is among the highest in the plastics sector. At present, PC/ABS alloying research has become a hot spot in polymer alloy research.