Wuhan Handern reinforced PVC transparent hose
DATE：2020/6/1 8:35:33 / READ： / SOURCE：This station
Wuhan Handern reinforced PVC transparent hose
1. Enhanced hose structure www.handern.com Cast film equipment
The reinforced hose pipe wall has a 3-layer structure, and the inner layer and the outer layer are soft PVC. The middle interlayer is a chemical fiber reinforced net wound into a grid. 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 acids, alkalis and oils) In recent years, it has been widely used in various industries such as mechanical pneumatic transmission, chemical gas, mining, water heaters, gardening, construction, etc. in China. www.handern.com Cast film equipment
2. Material selection and formula design
(1) Transparent stabilizer. Since PNC reinforced hoses have high requirements in terms of transparency and strength, both of them should be considered in the selection of PVC resin. It is important to consider these two factors in the composition of the formula. The higher transparency makes the choice of stabilizers more restricted. In the trial production process, barium stearate, cadmium stearate and dibutyltin dilaurate stabilizer were mainly used. Although the formulation cost of barium acid and cadmium stearate is low, the transparency of the product is poor, showing a mist. This is mainly due to the higher melting point of barium stearate (> 200 ℃), which is not melted at ordinary processing temperatures. The transparency of dibutyltin dilaurate is much better than the former, the transparency has been greatly improved, and dibutyldilaurate has light stabilization, weather resistance and lubricity, so the use of dibutyltin dilaurate as the stabilizer is more ideal. www.handern.com Cast film equipment
(2) Flame retardant. In the formulation design of PVC reinforced hose, it is divided into flame retardant series and civilian ordinary series. The requirements of the flame retardant series are relatively high, requiring that the flame retardant can be applied 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, phosphate triester, etc. When these flame retardants are subjected to high temperatures and oxidants, 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 causes coking of the polymer surface and limits the contact with 02. Under the action of the generated polymetaphosphoric acid, it can also form a glassy coke layer. This coke layer can be kept constant at a relatively high temperature. In addition, when PVC decomposes to form HC, it can also interact with phosphorus flame retardant to form PC, PC, etc. They are non-combustible gas at high temperature and have high density, which can cover the plastic surface to cut off the supply of oxygen, so as to achieve the purpose of flame retardancy. Triphenyl phosphate is a kind of phosphoric acid which is not expensive and relatively easy to obtain. The effect is better. It is suitable to use it as a flame retardant. www.handern.com Cast film equipment
(3) Plasticizer. The selection of plasticizers in the formulation is also a key, considering both cost and product quality. Therefore, in the formulation design, according to the use 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 weight. Generally speaking, the larger the relative molecular weight, the higher the strength, but the worse the transparency of the product. In order to take into account these two indicators, it is appropriate to use type 3 to type 5 resin. www.handern.com Cast film equipment
(5) Brightener. Due to the poor purity of domestic PVC resin, after processing into products, they are slightly yellowish to varying degrees. This yellow color also has a certain relationship with the transparency and brightness of the appearance. The yellowing of transparent products affects the appearance quality of the products. Therefore, adding a small amount of ultramarine blue or phthalocyanine blue to the formula can play a role in whitening and greatly improve the appearance of the product. www.handern.com Cast film equipment
Author：admin