Structure and properties of the polyurethane and polyurethane foam synthesized from castor oil polyols

Abstract

Polyols were synthesized from castor oil with diethanolamine and triethanolamine at the molar ratios from 1:1 M to 1:3 M with the total hydroxyl value and amino value in the range from 291 to 512 mg KOH/g. Bio-based rigid polyurethane foams with good mechanical properties, a high closed-cell content and the renewable content in the range from 25.0 to 35.6 wt% were obtained. Polyurethane coatings’ tensile strength and modulus of elasticity are higher for the samples obtained from castor oil/diethanolamine polyols, but the highest elongation at break is for the polyurethane from castor oil/triethanolamine polyols. In the temperature range from 150°C to 350°C, the polyurethanes from castor oil/triethanolamine have lower weight losses than the polyurethane from castor oil/diethanolamine polyols. The presence of polyethylene glycol enhances the degradability of the bio-based polyurethane foams in the presence of fungi.

Synthesis and properties of polyurethane elastomers based on renewable castor oil polyols

“…In the last few years, castor oil has been used widely to prepare polyurethane products, including rigid foams, flexible foams, elastomers, coatings, and adhesives . As castor oil and its derived polyols bear long hydrophobic hydrocarbon chains, they can increase the hydrophobicity of soft segment (SS) and enhance the water resistance of the as‐prepared polyurethane products.…”

Rapeseed Oil as Renewable Resource for Polyol Synthesis

“…Natural oil polyols with primary hydroxyl groups can be synthesized by vegetable oil reacting with amino alcohols [13].…”

Bio-based Polyols and Polyurethanes

“…Two major modification pathways have been widely used to improve the properties and applicability of castor oil-based polyols for producing PUs with improved properties and wider applications. Their derived PU coatings exhibited higher tensile strengths (19.8-57.4 MPa) and glass transition temperatures (T g , 44.5-84.5°C) than those from an unmodified castor oil-based analogue (tensile strength: 14.1 MPa; T g : 18.6°C) [93]. The functionality and hydroxyl number of castor oil-based polyols can be increased by transesterification with glycerol, pentaerythritol, and other polyols [1], or amidation with diethanolamine [93].…”