Aqueous polyurethane dispersions were prepared with 4−10 wt % of functionalized polyhedral oligomeric silsesquioxanes (POSS) via homogeneous solution polymerization in acetone followed by solvent exchange water. The use as the initial allowed for facile incorporation both diamino and dihydroxy functional POSS monomers a reaction environment. After addition water removal acetone, stable unimodal particle sizes obtained. did not have significant effect on dispersion's properties; however,...

Poly(butylene adipate-co-terephthalate) (PBAT) was first chemically modified via free radical grafting with maleic anhydride (MA) and the MA-g-PBAT graft copolymer then used as a matrix material to obtain cellulose nanocrystal (CNC)-reinforced bionanocomposites reactive extrusion process accelerate efforts develop functional bioabsorbable polymer nanocomposites improved properties. The molecular structure of PBAT after chemical modification confirmed by 1H NMR FTIR spectroscopy....

Abstract There are many variables in the preparation of aqueous polyurethane (PU) dispersions. Carboxylic acid content, solid degree pre/postneutralization carboxylic acids, and chain extension all impact dispersion particle size, viscosity, pH, molecular weights, glass transition temperature. This study evaluated these on a given PU formulation prepared from isophorone diisocyanate, an aliphatic polyester polyol, dimethylol propionic acid, hexamethylene diamine with triethyl amine as...

Rheological behavior of waterborne polyurethane dispersions was investigated with small-amplitude oscillatory shear flow experiments over wide ranges concentration, degree neutralization, chain extension, and temperatures to accelerate efforts understand their film formation characteristics. The rheological properties these environmentally friendly were found be dependent on composition postneutralization. But the extension preneutralization observed have little effect at a constant (PU)...

Isothermal and nonisothermal kinetics studies of thermal-induced gelation for waterborne polyurethane dispersions have been investigated rheologically. The change in the viscoelastic material functions such as elastic storage modulus, G', viscous loss G'' complex dynamic viscosity, η* during process was evaluated accurately first time. isothermal reaction described using a phenomenological equation based on Malkin Kulichikhin model that originally developed predicting curing thermosetting...

Reinforced polyurethane−urea nanocomposite with reactive polyhedral oligomeric silsesquioxanes (POSS) has been prepared via environmentally friendly aqueous dispersion no organic solvent. Rheological behavior of this important class materials investigated as a function POSS concentration over wide range shear frequency and temperature (−100 to 230 °C). The functionalized diamino-POSS was reacted initially isophorone diisocyanate (the urethane hard segments) before adding the polyester diol...

Thermal-induced gelation for waterborne polyurethane dispersion has been studied rheologically under isothermal condition over a wide range of frequencies at different constant temperatures (55, 60, 65, and 70 °C). The elastic storage modulus, G', temperature in the vicinity gel point increases abruptly, magnitude elevation G' was found to be dependent. Similar behavior observed both viscous loss G'', complex dynamic viscosity, η*. point, tgel, determined from intersection tan δ vs time...

The creep behavior and solid melt linear viscoelasticity of novel polyamide 6 (PA6) nanocomposites reinforced with cellulose nanocrystals (CNCs) prepared via in situ anionic ring‐opening polymerization (ROP) were investigated to accelerate research efforts develop new polymeric materials improved properties for lightweight, load‐bearing applications. obtained results showed that incorporation relatively small amounts ≤ 2wt% CNCs into the PA6 thermoplastic matrix gave nanocomposite samples...

The use of synthetic and natural biodegradable plastics has been severely limited due to their strong sensitivity processing conditions such as temperature. object our research is develop novel thermoplastic compositions methods for making plastic articles reproducibly from soy protein isolate corn starch. This paper discusses viable protein-starch that can be extruded injection molded into various shapes sizes. thermal mechanical properties the indicate it may useful in many applications...

New polyimide nanocomposites containing organically modified montmorillonite (MMT), synthetic silicate (chrysotile) nanotubes (SNT), and zirconium dioxide (ZrO2) were prepared to investigate the influence of nanoparticle morphology on nanocomposite rheology mechanical properties under selected conditions that materials are likely encounter during use.The efficiency homogeneous dispersion nanoparticles in matrix was studied by measuring model oligoimides (OI) dispersions desired amounts...

The photopolymerization kinetics of mixtures containing a trithiol and trivinyl ether (in different molar ratios) with cationic photoinitiator were investigated by real-time infrared rheology. Using this combination methods to follow both chemical conversion rheological property development, clear picture physical development during the complete polymerization process is obtained. This represents first example thiol−ene radical/ene two-step hybrid in which thiol copolymerizes vinyl...