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Title
Abstract
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Introduction
Experimental Preparation of Soy Polyol
Results and Discussion
Conclusions
References
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Chemistry
Polymers and Plastics

Rigid polyurethane foams based on soybean oil

Profile image of Andrew GuoAndrew Guo

2000, Journal of Applied Polymer Science

https://doi.org/10.1002/(SICI)1097-4628(20000711)77:2<467::AID-APP25>3.0.CO;2-F
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Abstract

Both HCFC-and pentane-blown rigid polyurethane foams have been prepared from polyols derived from soybean oil. The effect of formulation variables on foam properties was studied by altering the types and amounts of catalyst, surfactant, water, crosslinker, blowing agent, and isocyanate, respectively. While compressive strength of the soy foams is optimal at 2 pph of surfactant B-8404, it increases with increasing the amount of water, glycerin, and isocyanate. It also increases linearly with foam density. These foams were found to have comparable mechanical and thermoinsulating properties to foams of petrochemical origin. A comparison in the thermal and thermooxidative behaviors of soy-and PPO-based foams revealed that the former is more stable toward both thermal degradation and thermal oxidation. The lack of ether linkages in the soy-based rather than in PPO-based polyols is thought to be the origin of improved thermal and thermo-oxidative stabilities of soy-based foams.

FAQs

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What are the key mechanical properties of soy-based polyurethane foams?add

The study reveals that soy-based foams exhibited compressive strengths ranging from 100-150 kPa, which surpassed those of conventional PPO-based foams.

How does the viscosity of soy polyols affect foam formulation?add

Soy polyols initially have a viscosity of 6,000-11,000 mPa·s, but this can be reduced to below 1,000 mPa·s after blending with other ingredients.

What role does glycerin play in soy-based foam performance?add

Glycerin serves as an essential crosslinker, with optimal amounts between 10-25 pph resulting in minimal visual shrinkage and increased compressive strength.

What factors influence the thermal stability of soy-based polyurethane foams?add

The soy foams demonstrate improved thermal and thermo-oxidative stability at temperatures up to 260°C compared to PPO-based foams, owing to their hydrocarbon links.

How does foam density affect the compressive strength and insulation properties?add

Compressive strength increases with foam density, while thermal insulation decreases, showing typical relationships observed in conventional rigid foams.

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  23. SOYBEAN OIL-BASED RIGID POLYURETHANE FOAMS

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