Wuhan Handern Enhanced PVC Transparent Hose
DATE：2020/8/31 9:03:14 / READ： / SOURCE：This station
Wuhan Handern Enhanced PVC Transparent Hose
The wall of the reinforced hose is a three-layer structure, the inner and outer layers are soft PVC. The middle interlayer is a chemical fiber reinforced mesh wound into a square mesh. It has excellent chemical and mechanical properties, and is widely used in the transportation of pressure and corrosive gases and liquids (such as oxygen, chlorine, coal gas, dilute acid, alkali and oil, etc.). In recent years, it has been widely used in various industries such as mechanical pneumatic transmission, chemical gas, mining, water heater, gardening and construction in China. www.handern.com Cast film equipment
2. Material selection and formula design
(1) Transparent stabilizer. Since PNC reinforced hose has higher requirements in terms of transparency and strength, it is necessary to give consideration to both in the selection of PVC resin. These two factors should be considered in the composition of the formula. The high transparency restricts the selection of stabilizers. In the trial production process, barium stearate, cadmium stearate and dibutyl tin dilaurate stabilizers are mainly used. Although the formula cost of barium stearate and cadmium stearate is low, the transparency of the products is poor and the product is foggy. This is mainly due to the high melting point of barium stearate (>200°C) and it does not melt at normal processing temperatures. The transparency of dibutyltin dilaurate is much better than the former, and the transparency is greatly improved. Moreover, dibutyl dilaurate has light stabilizing effect, good weather resistance and lubricity, so dibutyltin dilaurate is used as a stabilizer. ideal. www.handern.com Cast film equipment
(2) Flame retardant. In the formula design of PVC reinforced hose, it is divided into flame-retardant series and civilian common series. The flame retardant series formula requires high requirements, and the flame retardant is required to be applicable to both transparent products and PVC products. At present, only a few flame retardants such as iodates can meet the above requirements, such as: triphenyl phosphate Ester, tricresyl phosphate, tributyl phosphate and triester phosphate, etc. When these flame retardants are subjected to high temperatures and oxidizing agents, phosphoric acid is first generated. Because phosphoric acid has a strong dehydration effect, it can dehydrate the oxygen-containing polymer to form carbonaceous coke, which makes the polymer surface coking and restricts the contact with 02. Under the action of the generated polymetaphosphoric acid, a glassy coke layer can be formed. This coke layer can be kept constant at a relatively high temperature. In addition, when PVC decomposes to generate HC, it can interact with phosphorus flame retardants to form PC, PC, etc. They are non-combustible gases at high temperatures, with high density, which can cover the plastic surface to cut off the supply of oxygen, thereby achieving the purpose of flame retardancy. Trityl phosphate is a kind of phosphoric acid that is not expensive and relatively easy to obtain, and has better effects. It is very suitable to use it as a flame retardant. www.handern.com Cast film equipment
(3) Plasticizer. The choice of plasticizer in the formulation is also a key factor, considering both cost and product quality. Therefore, in the formulation design, according to the purpose of the product, dioctyl phthalate (DOP) and dibutyl phthalate (DBP) are used as plasticizers. www.handern.com cast film equipment
(4) Resin. There are many types of PVC resin according to the relative molecular mass. Generally speaking, the greater the relative molecular mass, the higher its strength, but the worse the transparency of the product. In order to take into account these two indicators, it is advisable to use Type 3 to Type 5 resin. www.handern.com Cast film equipment
(5) Brightener. Due to the poor purity of domestic PVC resins, after processing into products, they all appear slightly yellow to varying degrees. This yellow has a certain relationship with transparency and appearance brightness. The yellowing of transparent products affects the appearance quality of products. Therefore, adding a small amount of ultramarine blue or phthalocyanine blue to the formula can have a whitening effect and greatly improve the appearance of the product. www.handern.com Cast film equipment
(6) Confirmation of formula. Through multiple tests on the machine and continuous optimization, while taking into account the cost and product quality, the best formulations of the two series of flame retardant and ordinary PVC reinforced transparent hoses have been selected. www.handern.com Cast film equipment
Author：admin