With the continuous development of processed products, the development of polyvinyl chloride PVC paste resin is very rapid. The demand for it in the international market is increasing day by day, and the development and utilization prospects are also very broad. It can be widely used in industrial and automotive fields, packaging and decoration fields, daily necessities and toys fields, medical and health fields, etc.
(1) Industrial and Automotive
- Automotive interiors: such as soft coatings for dashboards, door trim panels, and floor mats (high and low temperature resistance, anti-aging properties, and enhanced tactile feel).
- Industrial coatings: such as cable sheathing and equipment anti-corrosion coatings (leveraging their chemical resistance and insulation properties).
- Foam products: such as sound insulation and cushioning materials.
(2) Packaging and Decoration
Artificial/Synthetic Leather: Used in bags, sofas, and shoes (the surface is coated with PVC paste to simulate leather texture);
Wallpaper/Wall Cloth: PVC paste is applied to a substrate (paper, non-woven fabric) via a scraping process, and dried to create a waterproof and wear-resistant decorative layer;
- Food Packaging Film: PVC emulsion resin can be combined with environmentally friendly plasticizers to produce flexible packaging films (such as plastic wrap and candy wrap).
(3) Daily Necessities and Toys
- Soft Toys: Dolls and inflatable toys are produced through a slush molding process (PVC paste is injected into a mold and heated to form).
- Household Goods: Anti-slip mats, bathroom curtains, and tablecloths (utilizing its waterproof and stain-resistant properties).
(4) Medical and Healthcare
- Medical Products: Disposable gloves and IV tubing (must meet medical-grade standards, be heavy metal-free, and have low migration properties);
- Fitness Equipment: Yoga mats and sports protective gear (soft, non-slip, and age-resistant).
1. Microsuspension method
First of all, make a part of VCM (5%) into a stable emulsion (with a particle size of about 1.0 μm) by mechanical homogenization, and then carry out polymerization (an oil-soluble initiator must be selected). The PVC paste resin produced by this method has excellent fluidity, less emulsifier consumption, and improved thermal stability and water resistance of the resin.
2. Emulsion method
The emulsion polymerization formula mainly includes VCM, water, water-soluble initiator and emulsifier. In particular, emulsion polymerization requires very strict stirring, and the initiation is carried out in the water phase, and the commonly used initiator is water-soluble persulfate. Generally, the latex particle size obtained by emulsion polymerization is less than 0.2 μm. In order to achieve the purpose of increasing the latex particle size, the emulsion seed polymerization method was developed to increase the latex particle size to about 1.0 μm.
In emulsion polymerization, if there is already generated high polymer latex, control the material ratio and conditions. In principle, VCM only polymerizes on the generated latex particles, and no longer forms new particles; this generated high polymer latex The polymer latex is like a seed crystal, hence the name “emulsion seed polymerization”. But only a reasonable particle size is not enough, it must have an appropriate particle size distribution in order to obtain a PVC paste resin with excellent performance.
3. The mixed method
The mixed production process mainly integrates emulsion polymerization and microsuspension polymerization. In the whole reaction process, seeds after emulsion polymerization, other emulsifiers, initiators, various auxiliary agents and VCM are added to participate in the reaction. The mixing method uses C16 and C18 mixed linear alcohols and sodium lauryl sulfate or lauric acid amine to form an emulsifier to form a micro-emulsion, and the polymerization reaction is mainly carried out in micro-droplets. Adding seeds after emulsion polymerization makes the overall particle size distribution bimodal.