In practical applications, very few plastics can fully meet the specific application requirements, it requires us to make some appropriate adjustments to the physical properties of plastics. On the other hand, we need reduce costs as much as possible according to the actual situation of the market. So that you can take the lead in fierce competition!
The following four points you must know about the plastic.
1. How to reduce the cost of plastics?
1）Filling of inorganic substances
For thermoplastics, what we do is to reduce costs mainly. In addition to reducing costs, filling can also improve certain properties of the products. Generally, it can be improved in rigidity, heat resistance (inorganic filler), dimensional stability, reduction in mold shrinkage and creep resistance, and some can also improve insulation, flame retardancy, smoke odor, and sound insulation.
- CaCO3 filler
- Talc filler
- Wollastonite filler
- Kaolin filler
- Mica filler
- Diatomite filler
Points of formula design:
- Oil absorption of the packing
When the liquid auxiliaries are contained in the formulation system, a filler having a small oil absorbing property is used.
- The resin absorption of the filler
When the liquid resin is contained in the formulation system, a filler having a small resin permeability is used.
2)Low-cost resin blending
The cost of blending to reduce plastics refers to the process of mixing low-priced resins or waste plastics into high-priced resins to achieve cost reduction. Compared with the cost of filling down the plastic, the cost is not very large, but it has the advantage of less impact on its own performance.
Among the resins used, the relatively low-priced resins are mainly PVC, LDPE, LLDPE, HDPE, PP and PS. The so-called blending of inexpensive resins is incorporated into these resins.
2.How to enhance plastic?
Plastic added fiber reinforcement
The plastic addition fiber reinforcement method is one of the most common and effective reinforcement methods. Reinforcing fiber materials are the most important reinforcing materials for plastics, and can be used in an amount of more than 90% of the total reinforcing materials. Reinforced fiber materials include fiber and whisker. The specific varieties mainly include:
- Inorganic: such as glass fiber, asbestos fiber, carbon fiber, whisker, quartz fiber, graphite fiber and ceramic fiber;
- Organic: such as PAN fiber, polyethylene fiber, PA fiber, PC fiber, PVC fiber and polyester fiber;
- Metals: such as boron fiber and metal whiskers such as aluminum, titanium and calcium.
3.How to change the heat resistance of plastics?
Among all the fillers, most of the inorganic mineral fillers can significantly increase the heat resistance temperature of the plastic except for the organic filler.
Commonly used heat-resistant fillers are: calcium carbonate, talc, wollastonite, mica, calcined clay, bauxite and asbestos. For example, mica can be used at temperatures up to 1000 degrees Celsius and is the most effective heat-resistant modified filler.
The enhancement of plastics changes the heat resistance better than filling, mainly because most of the fibers have a very high heat resistance temperature and a melting point of more than 1500 degrees Celsius.
Commonly used heat-resistant fibers are: asbestos fiber, glass fiber, carbon fiber, whisker, polyamide fiber and acrylate fiber.
4.How to improve the flame retardancy of plastics?
The flame retardancy of most plastics is not very good. To measure the flame retardancy of the resin, the following indicators are generally used:
- Oxygen Index (OI)
- American UL Standard (UL-94)
The test method in the US UL standard is to observe the burning condition of the plastic when it is directly in contact with the fire source, and to analyze the flame resistance.
- V-0 level extinguished within 10s after the fire, does not ignite the 30cm cotton wool below it
- V-1 is extinguished within 10-30s after fire, and does not ignite the cotton wool 30cm below it
- V-2 level extinguished within 30s after fire, but can ignite the cotton wool 30cm below it
Flame retardant material for plastic addition
The commonly used composition in plastic-added flame retardant formulations is a flame retardant, which is an additive that prevents plastic from igniting or inhibiting flame propagation. Flame retardants are commonly used additives in plastic formulations, and their consumption is second only to fillers and plasticizers. There are many types of flame retardants, and thousands of them have been reported so far, and more than 100 kinds have been used frequently.
The commonly used flame retardants can be classified into halogen compounds, phosphorus compounds, nitrogen compounds, organosilicon compounds and various inorganic substances such as AI(OH)3, Mg(OH)2 and Sb2O3.
Professional plastic compounding production machine: Parallel twin screw compounding extruder line. More information, welcome to contact China Kerke company. Email: [email protected]