Microcellular Thermosetting Polyurethane Foams
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C. Brondi
Abstract
Thermosetting polyurethane foams are nowadays produced with typical bubble size, d > 150 μm, with plenty of room for improvement towards the cellular structure refinement, to gain, among others, in the thermal insulation performances. We herein report a first example of a microcellular thermosetting polyurethane foam, i. e. with bubble size below 5 μm, produced via the gas foaming technology. In particular, high-pressure CO2, N2 and their mixtures were utilized as blowing agents: solubilized separately into the polymer precursors, they were brought into a supersaturated state by a pressure reduction to induce the bubble nucleation and growth. To achieve microcellular foams, we made use of a novel two-stage pressure reduction program, concurrent to the polymer curing. The first stage is a pressure quench O (10–2 s) from the saturation pressure to an intermediate pressure to induce the nucleation of a large amount of dense bubbles. The second stage is a slow O (102 s) further pressure decrease to ambient pressure, allowing for a slow bubble growth, designed to reach ambient pressure exactly when the curing reached completion.
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© 2020, Carl Hanser Verlag, Munich
Artikel in diesem Heft
- Contents
- Contents
- Regular Contributed Articles
- Study of Mechanical and Moisture Absorption Behavior of Epoxy/Cloisite-15A Nanocomposites Processed Using Twin Screw Extruder
- Fabrication of Poly Vinyl Acetate (PVAc) Nanofibers Using DMAC Solvent: Effect of Molecular Weight, Optimization by Taguchi DoE
- Effect of Poly(phenylene sulfide) (PPS) as Functional Additive on the Physical Properties of Poly(phenylene ether) (PPE)/PPS Blends
- Enhanced Dispersion and Mechanical Behavior of Polypropylene Composites Compounded Using Extension-Dominated Extrusion
- The Influence of Melt-Mixing Conditions and State of Dispersion on Crystallisation, Rheology and Mechanical Properties of PCL/Sepiolite Nanocomposites
- Experimental and Numerical Investigation on Indentation of Orthotropic Microplates with Finite Thickness
- Microcellular Thermosetting Polyurethane Foams
- Utilisation of Waste Plantain (Musa Paradisiaca) Peels and Waste Polystyrene in the Development of Reinforced Polymer Composites
- PPS News
- PPS News
- Seikei Kakou Abstracts
- Seikei Kakou Abstracts
Artikel in diesem Heft
- Contents
- Contents
- Regular Contributed Articles
- Study of Mechanical and Moisture Absorption Behavior of Epoxy/Cloisite-15A Nanocomposites Processed Using Twin Screw Extruder
- Fabrication of Poly Vinyl Acetate (PVAc) Nanofibers Using DMAC Solvent: Effect of Molecular Weight, Optimization by Taguchi DoE
- Effect of Poly(phenylene sulfide) (PPS) as Functional Additive on the Physical Properties of Poly(phenylene ether) (PPE)/PPS Blends
- Enhanced Dispersion and Mechanical Behavior of Polypropylene Composites Compounded Using Extension-Dominated Extrusion
- The Influence of Melt-Mixing Conditions and State of Dispersion on Crystallisation, Rheology and Mechanical Properties of PCL/Sepiolite Nanocomposites
- Experimental and Numerical Investigation on Indentation of Orthotropic Microplates with Finite Thickness
- Microcellular Thermosetting Polyurethane Foams
- Utilisation of Waste Plantain (Musa Paradisiaca) Peels and Waste Polystyrene in the Development of Reinforced Polymer Composites
- PPS News
- PPS News
- Seikei Kakou Abstracts
- Seikei Kakou Abstracts
