NKY® PVP K/VA64

Molecular structure of PVP         Molecular structure of VP/VA 64

NKY® PVP Specifications:

The basic properties of PVP K/VA64 are as follows:

Polyvinylpyrrolidone (PVP) is a high molecular weight compound produced by the polymerization of N-vinyl-2-pyrrolidone. It has good water solubility, film-forming ability, high molecular surface activity, and colloidal protective capacity, and is stable to acids and heat.

Vinylpyrrolidone vinyl acetate copolymer (VA64) is a high molecular weight compound copolymerized from N-vinyl-2-pyrrolidone and vinyl acetate at a ratio of 6:4. It essentially retains the properties of PVP and, due to the introduction of vinyl acetate, reduces the glass transition temperature of the polymer, endowing the compound with good thermal processing performance.

The main applications of PVP K/VA64 are as follows:

1 Film-forming agent in seed coatings.

The film-forming agent is an important component in pesticide seed coatings. It allows air and a moderate amount of moisture to pass through, maintaining the vital functions of the seeds, ensuring normal germination and growth of seedlings, and also enabling the slow release of pesticides and seed fertilizers contained within, ensuring protection from pests and diseases for an extended period, promoting seedling growth, and increasing crop yields.

Adding PVP K/VA64 to the seed coating formula for seed coating can reduce the film detachment rate of coated seeds without affecting the germination rate of the seeds. Therefore, it can be applied to the product formula of seed coatings, with a common addition amount of 3~10%.

2 Pesticide Solid Dispersions.

In the field of pesticides, the solid dispersion technology of PVP K/VA64 is used to improve the solubility and dissolution rate of poorly soluble pesticides. Solid dispersion technology can enhance the solubility and release rate of ester-based insoluble pesticides, such as abamectin, indoxacarb, and beta-cypermethrin. For instance, in some studies, solvent-melting method and solvent method were used to prepare solid dispersions of insoluble pesticides and PVP. The results showed that solid dispersion technology can significantly increase the solubility of these pesticides; for example, the solubility enhancement of indoxacarb-PVP solid dispersion reached 45.5 times. The common dosage is 1 to 20 times the mass of the pesticide.

3 Fertilizer Carrier.

The C=O on the main chain of PVP K can bond with more -OH groups through hydrogen bonding. By modifying polyvinyl alcohol (PVA) through solution blending and adding distiller's grains to prepare a composite coating material, it is possible to encapsulate nitrogen fertilizer to create slow-release fertilizers. The components are compatible and bond together through hydrogen bonding. The copolymerization of the two significantly improves the physical properties of the film material, resulting in a marked enhancement in the thermal stability of the composite film material. Moreover, the slow-release fertilizer exhibits good release performance. By adjusting the ratio of PVP K in the composite coating material, the release rate of nitrogen in the slow-release fertilizer can be controlled, extending the fertilization period to 80-100 days. This effectively reduces fertilizer loss and improves the utilization rate of fertilizers.

4 Coating Preservation.

Coating preservation technology involves using high molecular weight substances with good film-forming properties, dissolving them in water or other solvents, and preparing a solution of certain concentration to spray or coat on the surface of fruits and vegetables, forming a semi-permeable membrane with protective effects. By covering and encapsulating the surface of the fruits and vegetables, this technology can effectively reduce the respiration intensity of the harvested fruits and inhibit water loss. At the same time, the film separates the fruits from the external environment, greatly reducing the contact between the fruits and the external environment, reducing oxidation of the fruits and the rate of infection by harmful microorganisms, thus achieving the purpose of preservation and antibacterial. Additionally, utilizing the good complexing ability of PVP K/VA64, it can inhibit the activity and expression of enzymes related to ethylene production on the surface of the fruits, effectively suppressing the respiration intensity of the fruits, delaying the appearance of the respiratory peak, reducing the loss of nutrients, and thus achieving the effect of preservation. The common dosage is 0.5 to 5%.