Biomass Polyester Polyol Envelope for Degradable Controlled-Release Fertilizer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing controlled-release fertilizers face challenges with high production costs, poor degradability, and limited scalability due to the use of expensive thermoplastic and thermosetting resins, which hinder their widespread application in agriculture.
Innovation Solution
A polyester polyol with a high biomass ratio is used to create a polyurethane controlled-release fertilizer envelope by cross-linking with MDI, utilizing epoxy soybean oil and small molecular polyol derived from biomass, resulting in a degradable and cost-effective material.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If thermoplastic resin or thermosetting resin is used for envelope material, then controlled-release function is achieved, but production cost increases significantly
Solution Approach 1:
The patent changes the chemical composition parameters of the envelope material from conventional thermoplastic/thermosetting resins to polyester polyol-based polyurethane system. This parameter change maintains the controlled-release function through polyurethane formation while significantly reducing material costs by using polyester polyol as a more economical alternative to traditional resins.
Solution Approach 2:
The patent employs a composite material system combining polyester polyol with crosslinking agents to form polyurethane envelope material. This composite approach achieves the desired controlled-release properties and mechanical strength while reducing dependency on expensive conventional resins, thereby lowering production costs.
2Strength
If conventional resin envelope materials are used, then envelope strength is maintained, but degradability and environmental friendliness deteriorate
Solution Approach 1:
The patent changes the chemical structure parameters of the envelope material by using polyester polyol as the base component instead of conventional petroleum-based resins. Polyester polyol is derived from renewable resources and exhibits better biodegradability, thus improving environmental compatibility while maintaining adequate envelope strength through polyurethane crosslinking.
Solution Approach 2:
The patent adopts a disposable envelope material design where the polyester polyol-based polyurethane envelope degrades after serving its controlled-release function. This approach prioritizes environmental friendliness and degradability over long-term durability, allowing the envelope to break down naturally after nutrient release is complete.
3Reliability
If solvent-based thermoplastic resin is used for enveloping, then good nutrient release function is achieved, but production complexity and cost increase
Solution Approach 1:
The patent extracts and eliminates the solvent component from the traditional thermoplastic resin enveloping process. By using polyester polyol that can form polyurethane envelopes through crosslinking without requiring solvents, the process is simplified while maintaining effective nutrient release control.
Solution Approach 2:
The patent replaces the solvent-based chemical system with a crosslinking-based chemical system. Instead of using solvents to dissolve and apply thermoplastic resin, the invention uses polyester polyol that crosslinks to form the envelope structure directly, simplifying the production process and eliminating solvent-related complexity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The new envelope material is environmentally friendly, highly degradable, and provides controlled nutrient release for up to 60-150 days, reducing production costs and environmental impact while maintaining effective nutrient delivery.
Implementation Method 1
cross-linking with MDI, utilizing epoxy soybean oil and small molecular polyol derived from biomass
Implementation Method 2
highly degradable, and provides controlled nutrient release for up to 60-150 days
Data Source
AI summary
Epoxy soybean oil polyol is firstly prepared by open-ring etherification of an epoxy soybean oil and a small molecular alcohol with an organic acid catalyst, and then the epoxy soybean oil polyol is further esterified with an organic acid under an esterification catalyst to prepare a polyester polyol with a high biomass ratio. The polyester polyol includes a compound having an Ñ-type structure and a compound having an Ò-type structure. A method for preparing the polyester polyol is provided, as well as a polyurethane controlled-release fertilizer envelope and a polyurethane controlled-release fertilizer prepared by cross-linking the polyester polyol and MDI on surfaces of the fertilizer. The epoxy soybean oil and the small molecular alcohol can be derived from biomass, so a biomass content is high, the synthesized product is environmentally safe, and product performance is excellent.