Hydrolysis of abandoned bovine hair by pulping spent liquor and preparation of degradable keratin-based sprayable mulch film

Pulping spent liquor was used to hydrolyze abandoned bovine hair, and the resulting keratin hydrolyzate was blended with polyvinyl alcohol (PVOH), polyacrylamide (PAM), N,N-methylenebis (acrylamide) (MBA), and glycerol (GL) to prepare the low-cost degradable keratin-based sprayable mulch film (KSMF). The prepared KSMF contained elements required for plant growth, such as N, P, K, S, Ca, Si, and the water absorbency reached 380% in deionized water. A degradation of 23.1 wt% was attained while it was buried for 50 d in soil. The KSMF was easy to apply and needed to be diluted for spraying on the soil surface and formed a physical barrier to reduce evaporation of water and heat preservation. The KSMF had good degradability and entered the soil to become a high-quality biomass organic fertilizer during the growth of the crop, thus avoiding “white pollution” and realizing the recycling of waste, which would extend the application prospects in sustainable modern agriculture.