The present paper proposes to investigate the links between the microstructure of polyurethane foams and their sound absorbing efficiency, and more specifically the effect of membranes closing the cells. This study is based on the complete characterization of 15 polyurethane foam with various cell sizes and reticulation rates (i.e., open pore content): (i) characterization of the microstructure...

Bio-based high elastic polyurethanes were prepared from hexamethylene diisocyanate and various ratios of isosorbide to poly(tetramethylene glycol) as a diol by a simple one-shot bulk polymerization without a catalyst. Successful synthesis of the polyurethanes was confirmed by Fourier transform-infrared spectroscopy and (1)H nuclear magnetic resonance. Thermal properties were determined by diffe...

Controlled degradability in response to the local environment is one of the most effective strategies to achieve spatiotemporal release of genes from a polymeric carrier. Exploiting the differences in reduction potential between the extracellular and intracellular environment, disulfides are frequently incorporated into the backbone of polymeric drug delivery agents to ensure efficient intracel...

ORGANOHALOGEN COMPOUNDS – Volume 66 (2004) 138 Introduction Polyurethane foam (PUF) samplers are being used in an increasing number of studies to passively sample semivolatile organic compounds (SOCs) in the atmosphere (e.g. 1, ). However, recent research shows that the uptake and loss kinetics of passive air samplers is influenced by changes in wind speed . According to theory, the rate of che...

In the present paper, the sorption properties of caffeine (CAF) onto polyether type polyurethane foam (PUF) as solid phase sorbent were investigated with UV determination at 274.3 nm. Batch and column methods were used to optimize chemical, flow, kinetic and isothermal conditions for preconcentration of CAF. Results indicated quantitative sorption of CAF at pH 8 and 30 min shaking time. The max...

reaction to fire of fire-retarded rigid pur foams and two types of metal faced rigid polyurethane foam core sandwich panel was evaluated by using cone calorimeter test method. the tests were carried out in various radiative heat fluxes from 15 to 75 kw/m2. the radiation rate effect on reaction to fire parameters, including time to ignition (tti), peak of heat release rate (prhr), total heat rel...

in this paper, the focus is on a new kind of biodegradable semi-interpenetrating polymer networks, which derived from ɛ-caprolactone, lactide, 1,4-butane diisocyanate and ethylenediamine and also its potential has been investigated in soft tissue engineering applications. the polymers were characterized by nuclear magnetic resonance (nmr) spectrometry, fourier transform infrared spectroscopy (f...

New organic-inorganic polyurethane-based hybrids with enhanced mechanical properties and thermal insulation are reported. Polyurethane-based characterized by the intimate interactions of their inorganic organic co-networks prepared sol-gel approach, have exhibited exceeding those polyurethane foams, e.g. stability, durability insulating effectiveness. However, previously been poor. Here, new po...

Introduction: Attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy with a diamond ATR crystal was used to examine 41 historical polymer fragments and a selection of polyurethane fragments subjected to accelerated ageing. The advantages and limitations of FTIR data for polymer assessment is discussed. Moreover the efficacy of the data interpretation tool principal comp...