Synthesis, properties, and dyeing application of nonionic waterborne polyurethanes with different chain length of ethyldiamines as the chain extender

Abstract

This study deals with the synthesis of some nonionic waterborne polyurethanes (PUs), using ethyldiamines of different chain length, such as ethylenediamine (EDA) and diethyltriamine (DETA), as the chain extender in the reaction, and examines the thermal properties, mechanical properties, and dyeing properties of the PU products and their blends. As far as each PU by itself is concerned, we found that the T g of the one made with DETA is the highest, followed by that with EDA, and the one with 1,4-butanediol (1,4-BD) is the lowest. The PU made with 1,4-BD as the chain extender has no T m , while the two others, using diamines as chain extenders, have a clear T m , the one with DETA being higher than that with EDA. However, the enthalpy data are just the opposite. The tensile strengths of the two PUs, made with diamines as the chain extender, are larger than that made with 1,4-BD, but their respective elongation properties are just the opposite. A comparison within PUs made with diamines showed that the one made with EDA is greater in both strength and elongation categories than that made with DETA. However, the one made with DETA is far superior to both of those made with 1,4-BD and EDA in their dyeexhaustion ratio, color yield (K/S), fixation rate, and color fastness. In respect to the various PU mixtures that we examined, we found that both PUs synthesized with EDA or DETA as the chain extender would have their T g 's greatly increased by blending in some PU made using 1,4-BD as the chain extender. Among them, in particular, a blend of PU, made separately with DETA and 1, 4-BD as the chain extender, showed great improvements in both tensile strength and elongation and also demonstrated better dyeability.

Polyurethaneurea aqueous dispersions prepared with diethyltoluenediamine as chain extender

“…It was found that the water absorption of PU film prepared with the L-lysine was higher than those of other films, but it showed the smallest hydrolysis weight loss among the three samples. Yen et al 7 studied the mechanical properties of several waterborne PUs prepared with different diamines or diols as chain extenders, such as EDA, diethyltriamine, and 1,4-butanediol, and found that the mechanical properties of the PUs prepared with diamine as chain extender were better than those prepared with 1,4-butanediol. Delpech and Coutinho 8 also studied the influence of various chain extenders on the properties of the waterborne PUs and found that the EDA-extended PU film exhibited better mechanical properties than the hydrazine-extended one.…”

Design, characterization, dyeing properties, and application of acid-dyeable polyurethane in the manufacture of microfiber synthetic leather

“…This consequently leads to low dye uptake and unstable binding of the acid dyes to the polyurethane matrix that not only result in uneven coloration and poor color fastness, but also account for high dye discharge in effluents, thus posing serious environmental threats [15]. More importantly, because of the difficulty in efficiently dyeing ordinary polyurethane, more than one dyestuff is required to dye microfiber synthetic leather that complicates the dyeing process and compromises the color uniformity of the final products [16][17][18][19]. Thus, improving the dyeing properties of polyurethane toward acid dyes is crucial for fabricating microfiber synthetic leather with satisfactory uniformity and highly realistic appearance.…”

Synthesis of waterborne polyurethane containing alkoxysilane side groups: Study on spacer linkages

“…It has been found in the solvent‐based PU that the introduction of a proper amount of urea groups in a diol extender system would make a positive contribution to the mechanical properties of the resulting PU materials. The reason lies in the increased intermolecular hydrogen‐bonding interactions …”

“…The reason lies in the increased intermolecular hydrogen-bonding interactions. 12 In our previous work, 13 we reported an alkoxysilane-modified diol extender (DEA-Si) in which the trimethoxysilane group was connected to the diethanolamine structure by an alkyl-ester segment. Here, in order to further improve the aggregating strength of WPU film, we substituted the ester linkage with the urea linkage and synthesized a new diol-bearing pendant ureapropyl trimethoxysilane (APD-Si).…”