What are the influencing factors responsible for the fading of plastic EVA products?I believe that many people are very worried about EVA products will appear such problems, in fact, EVA as the current heart material appears in home life, it often acts as sound insulation materials, ground materials, buffer materials and so on appear in the decoration engineering.EVA materials have many benefits as a carpet, such as, for example, excellent earthquake resistance, waterproof, electricity and so on.So today Guohui process products with us to summarize the four reasons why plastic EVA products fade:
The ements affecting the fading of plastic EVA products, the fading of plastic color products is related to pigments, dye light resistance, oxygen resistance, heat resistance, acid and alkali resistance and properties of the resin used.The main material shall not be selected after the above functions of the required pigment, dye, surfactant, dispersion agent, carrier resin and anti-aging aid are generally evaluated according to the processing conditions and application requirements of the plastic products.
First: four reasons for the fading of plastic EVA products:
1, fading of acid and alkali resistance to coloring plastic products is related to its chemical resistance (acid and alkali resistance, oredox resistance).
For example, molybdenum chromium red is resistant to dilute acid, but sensitive to alkali and cadmium yellow acid. These two pigments and phenolic resins play strong reduction effects on some pigments, which seriously affect the heat and weather resistance of the pigments and fade.
2, antioxidant Some organic pigments fade after the degradation of large molecules or other changes after oxidation.
This process is high temperature oxidation in processing, the other is oxidation in strong oxidants (such as chromate root in chromium yellow).Lake, azo pigment and chrome yellow mixing, red will gradually decrease.
The thermal stability of 3, heat-resistant pigments refers to the degree to which the pigments heat lose weight, discoloration and fade at the processing temperature.
The components of inorganic pigments are metal oxides and salts, with good thermal stability and high thermal work resistance.The pigments of organic compounds will undergo molecular structure changes and a small decomposition at a certain temperature.In particular, for PP, PA, PET products, the processing temperature is above 280℃. When selecting the colorant, attention should be paid to the heat resistance of the pigment, on the one hand, the heat resistance time of the pigment should be considered, and the heat resistance time is 4-10rain.
Light resistance of 4, resistance pigments directly affects the fading of products.
Outdoor products illuminated by strong light, the light resistance (sun resistance) level of coloring used is an important indicator, light resistance grade difference, the products will quickly fade in application.The light resistance grade of weather resistance products shall not be lower than six, it is best to choose seven or eight, and indoor products can choose four and five.The light resistance function of the carrier resin also has a great effect on the color change, and the molecular structure caused by ultraviolet light changes and fades.Participating in optical stabilizers such as ultraviolet absorbers in the mother material can improve the light resistance work of coloring agents and coloring plastic products.
Ferrari EVA Watch Box
Second: EVA materials generally have the following 6 characteristics.
1, Water resistance: closed bubble hole structure, no water absorption, moisture resistance, water resistance work is excellent.
2, Corrosion resistance: corrosion resistance to seawater, oil, acid, alkali and other chemicals, antibacterial, non-toxic, tasteless, pollution-free.
3, machining: no joint and easy to heat pressure, cutting, coating and paste.
