2014年1月25日星期六

What is Polyvinyl Alcohol Resin?

Polyvinyl Alcohol Resin products is white solid, the appearance can be divided into three kinds: flocculent, granular and powder. PVA Resin is non-toxic, tasteless, non-polluting, and can be dissolve in water at the temperature of 80 to 90 . The aqueous solution of Polyvinyl Alcohol Resin has good adhesion and film forming properties, it has resistant to oil, lubricants and most organic solvents such as hydrocarbons. Polyvinyl Alcohol PVA has the properties of long-chain polyol esters, ethers, acetals and other chemical properties.
At the same time of preparation of aqueous solutions, this product is not bubbling, but in high concentration, speed faster and also produce small amounts of foam in order to contain the bubble, we should add defoamer: 0.01-0.05% (PVA as a benchmark) octanol, phosphoric acid tributyl ester or 0.2-0.5% (PVA as a benchmark) silicone emulsion.
Anti-corrosion: If the Polyvinyl AlcoholResin has been long-term storage, the water in aqueous solution will have a corruption, but it does not affect the performance of this product. At this point, we should add 0.01-0.05% (PVA as a benchmark) of formaldehyde, salicylic acid or other preservatives.
Rust prevention: Storage in tools, you should add traces of weak bases, should be added when meat is used 0.02-0.05% (PVA as a benchmark) of sodium nitrite, the best use of stainless steel, plastic containers.
And the Polyvinyl Alcohol Resin should be stored in ventilated, cool and dry place, away from sources of ignition. And should handle with care during transport, and prevent damage to the packaging.

Polyvinyl acetate emulsion (PVAC) is mainly based on vinyl acetate monomer, polymer, commonly known as the white LaTeX. The latex-free environment, the price is cheap, easy to use, are porous materials such as wood, paper, fiber adhesive ideal for. It is widely used in printing, bonding, wood construction, leather, tobacco processing, paper processing, fiber composite, aluminum foil paper, Emery cloth, sand paper adhesive industry, can also be used for insulating plates for interior wall paint, steel processing and so on.

2014年1月15日星期三

The Characteristics of PVC Resin.


PVC Resin is one of the most important organic synthetic materials. The full name of it is Polyvinyl Chloride Resin. This product has good physical properties and chemical properties, and is widely used in industrial, construction, agriculture, daily life, package, electric power and public utilities and many other fields.
The physical appearance of PVC Resin is white powder, non-toxic and odorless. The relative density of it is 1.35 to 1.46, the refractive index of it is 1.544 (20 ). PVC Resin is insoluble in water, gasoline, alcohol and vinyl chloride, but it can be soluble in acetone, ethylene dichloride, xylene solvent and so on. PVC Resin has high chemical stability and good plasticity.
Except for a few organic solvent, it can resistant to any concentration of hydrochloric acid, concentration below 90 % of nitric acid, concentration about 50 % to 60 % of sulfuric acid and concentration below 20 % caustic soda at the room temperature. In addition to these, it is fairly stable for the salt. PVC and burns on the flame and release HCl, but leave the flame self-extinguishing, is a kind of self-extinguishing and fire products. PVC start to break down and slowly release HCl when the temperature is above 100 . As the temperature rises, the speed of decomposition and release HCl rising, the PVC color start to change.
PVC is made by free radical polymerization of vinyl chloride synthesis. By suspension polymerization and emulsion polymerization method and polymerization method, dominated by suspension polymerization, accounted for about 80% of PVC production. PVC production in the industry based on vinyl chloride monomer acquisition method to distinguish, can be divided into calcium carbide method, ethylene method, imports (EDC and VCM) simplex method.
According to the different methods of production, PVC pure powder can be divided into general purpose PVC Resin, high degree of polymerization PVC Resin, crosslinked PVC Resin. General purpose PVC Resin is made of vinyl chloride monomer in the initiator role of aggregation formation. High degree of polymerization of PVC Resin is in the vinyl chloride monomer polymerization system include chain growth agent in polymer made of resin. Crosslinked PVC Resin is added in the vinyl chloride monomer polymerization system containing diene and polyene resins, crosslinking agent aggregation.