A kind of controlled-release fertilizer coating material based on C36 dimer fatty acid polyester polyol and preparation method thereof

Abstract

The invention relates to a controlled-release fertilizer coating material based on C36 dimer fatty acid polyester polyol, which is prepared by mixing and reacting 50-75 wt% of material A and 25-50 wt% of material B at 65-85 DEG C. The material A is C36 dimer fatty acid polyester polyol and / or soybean oil polyalcohol; and the material B is isocyanate. The C-36 fatty acid polyester polyol used as the raw material has the advantages of wide sources, simple synthesis technique, low cost, high water resistance, high temperature resistance and high flexibility; and thus, the prepared coating material has the advantages of favorable elasticity, favorable hardness and high controlled-release performance. The proportion of the film material to the core fertilizer can be changed to prepare controlled-release fertilizers with different release periods. Abundant microbes capable of degrading aliphatic polyester exist in the natural world; and the C36 fatty acid polyester polyol coating material can be self-degraded in soil, can not pollute the plants and environment after long-term usage, and thus, is green and environment-friendly.

Description

technical field [0001] The invention relates to a controlled release fertilizer coating material based on C36 dimerized fatty acid polyester polyol and a preparation method thereof, belonging to the technical field of slow and controlled release fertilizers. Background technique [0002] With the development of the country's political economy and culture, the low utilization rate of traditional fertilizers and serious pollution problems have become increasingly prominent. More and more domestic and foreign countries are focusing on the research of new fertilizers such as slow and controlled release fertilizers. For example: in a series of patents by William P. Moore (US4711659, US4969947, etc.), a controlled-release fertilizer is firstly formed by chemical bonding with the fertilizer to form a first layer of coating, and then a polyurethane material is used for the second layer of coating. Alice P.Hudson (US5538531) patent clearly describes the use of isocyanates and polyols...

AI Technical Summary

Problems solved by technology

[0005] The mixing degree of isocyanate component and polyol component of polyurethane resin coating material on the surface of fertilizer granules is low, and the utilization rate of coating material is low; the viscosity of the coating material increases during the transition from liquid to solid state. Without the action of anti-adhesive solvent, it is easy to have problems such as uneven coating, unwrapping, and wire drawing during the curing process, which will affect the controlled release performance of the fertilizer.

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