Polyurethanes (PUs) constitute one of the most versatile class of polymers with respect to composition, properties, and applications. Having an excellent elastomeric performance, PUs has been used in a wide range of applications. Additionally, silane terminated modified polyurethanes (STPUs) combine advantageous characteristics of PUs and organosilicon. Two PUs and four STPUs modified by a silane end‐capper N‐ethyl‐3‐trimethoxysilyl‐2‐methylpropanamine and N‐cyclohexyl aminomethyltriethoxysilane were synthesized and acted as an adhesives or coatings which could be suitable for use in moisture‐curing compositions at room temperature without releasing CO2. The effect of isocyanate groups in the polyurethane backbone and organofunctional groups in the aminosilane structure (R1–NH–R2–Si[OC2H5]3), R1 (alkyl or aryl), the spacer R2 (α or γ) was examined. The chemical and physical structures of the PUs and STPUs were investigated by nuclear magnetic resonance (13C and 1H), dynamical mechanical analysis (DMA), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT‐IR) and the mechanical properties were evaluated by universal tensile tests. The results showed that STPUs were successfully synthesized as moisture curable, exhibiting low viscosity with adequate tensile strength and elongation can be prepared environmentally benign by utilizing secondary aminosilane end‐cappers and an optimal combination of the polyol molecular weight and NCO/OH ratio.
This study investigates the influence of triacrylate monomer structure on volume shrinkage, tensile properties, and viscosity of vat polymerization (VP) resins. The amount of triacrylate monomer kept constant as 20%wt. to prevent excessive volume shrinkage effect. Results indicated that ethoxylated and propoxylated triacrylate structures are beneficial to reduce the volume shrinkage of VP resins. However, these flexible chain structures led to a reduction in tensile properties and the elastic modulus of VP resins deteriorated up to 35% compared to trimethylolpropane triacrylate (TMPTA). There is no significant effect observed on VP resin reactivity according to the triacrylate type. Besides, ethoxylated triacrylate presented the best dilution effect on VP resin.
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