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Introduction Polyurethane elastomers Polyurethanes are polymers which are formed in a reaction between monomers that contain at least two isocyanate (–N=C=O) functional groups and other monomers that contain

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more easily oxidize in air or are protected by organic compounds [ 11 ]. However, experimental studies especially on the thermal conductivity of PMCs containing metal/metal oxide fillers are scarce. Polyurethanes (PUs) containing metal

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-biodegradable polymers [ 1 , 2 ]. For instance, lignin as part of the starting material, has been studied to produce different polymers, such as polyurethane (PU) [ 3 – 5 ], phenol-formaldehyde resin [ 6 , 7 ], polyester [ 8 , 9 ]. It can also be used for blending

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Abstract  

In this work thermal transitions and thermal stability of polyurethane intermediates and polyurethanes were investigated. The intermediates were obtained by glycolysis of waste polyurethane (PUR) in the reaction with hexamethylene glycol (HDO). The excess of HDO was not separated from the product after the glycolysis process was finished. The effects of different mass ratio of HDO to PUR foam on selected physicochemical properties (hydroxyl number, Brookfield viscosity and density) were also determined. The polyurethanes were synthesized from the obtained intermediates by the prepolymer method using diisocyanate (MDI) and glycolysis product of molecular mass in range 700/1000 g mol–1. Hexamethylene glycol, 1,4-butanediol and ethylene glycol were used as chain extender agents. Influence of NCO groups concentration in prepolymer on glass transition temperature (T g) and storage and loss modulus (E’, E’’) of polyurethanes were investigated by the DMTA method. Thermal decomposition of obtained glycolysates and polyurethanes was followed by thermogravimetry coupled with Fourier transform infrared spectroscopy. Main products of thermal decomposition were identified.

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Fireproofing of polyurethane by organophosphonates

Study of degradation by simultaneously TG/DSC

Journal of Thermal Analysis and Calorimetry
Authors: B. Youssef, B. Mortaigne, M. Soulard, and J. Saiter

Abstract  

In this work, we have studied the degradation processes of polyurethane containing phosphonate groups used as a fireproofing agent. These studies are undertaken by simultaneous thermogravimetry (TG) and differential scanning calorimetry (DSC) measurements. It is found that fireproofing agents with phosphonate react with oxygen in the air and prevent the complete combustion of the material. It is also found that the energy released during combustion is low when comparison is performed with other fireproofing materials.

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Abstract  

Equilibrium melting temperatures and crystallization parameters of polyamide 6/polyurethane blends were investigated. Thermal properties of the crystalline phase of blends obtained from polyamide 6 and polyurethane containing 40 wt% of hard segments, are only limited influenced by the overall blend compositon. Because from separate measurements single glass transitions for all samples were estimated, so in the investigated case the blending process may occur mainly between amorphous fraction of polyamide 6 and the polyurethane or, what is more probable, the polyurethane phase is dispersed in the continuous polyamide matrix, although some interactions exist.

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]. Compared with APP, the microencapsulated APP (MCAPP) coated with MF or UMF resin can be dispersed well in the PP matrix and has lower water solubility. Ni and co-authors have reported microencapsulated ammonium polyphosphate (APP) with polyurethane (MCAPP

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Journal of Thermal Analysis and Calorimetry
Authors: W. Sułkowski, A. Danch, M. Moczyński, A. Radoń, A. Sułkowska, and J. Borek

Abstract  

Granulated rubber obtained from used tyres, below 1.5 mm granularity (fine rubber) and polyurethane prepolymers (Chemolan M, Chemolan M50 and Chemolan B3) were used for the synthesis of rubber waste-polyurethane composites, containing 90, 85, 80, 75 and 70%w/w of fine rubber. The influence of the kind of polyurethane resin on hardness, elasticity, glass transition temperature and thermal stability of composites was studied. Kinetic parameters of the thermal degradation process of composites were calculated from thermogravimetric analysis (TG) data.

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are hydrophilic, which causes lack of adhesion and wettability. Therefore, fiber treatments, coupling agents and binders in the interface are used for a better adhesion. In this study, the researchers exploit the hydrophilicity of polyurethane that is

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Introduction Polyurethane (PU) is a class of extremely versatile technopolymers. Unfortunately, a prolonged service duration is compulsory connected with the necessity of PU’s thermo- and photostabilization due to a rapid self

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