Synthesis and characterization of nanocomposites of silicon dioxide and polyurethane and epoxy resin interpenetrating network

A thermoplastic polyurethane elastomer/silica hybrid (TPU/SiO 2 ) was prepared using the sol-gel process. This work was undertaken to investigate the thermal and physical properties of this type of hybrid by employing different catalyst systems during sol-gel processing. Two types of catalyst systems including acetic acid (HOAc) and hydrochloric acid (HCl) were used to prepare sol particles. The mixing of the sol solution and TPU solution was then carried out to form a TPU/silica hybrid. Fourier transform IR spectra and dynamic mechanical properties were recorded to depict the enhanced interfacial interaction. Thermogravimetric analysis was used to determine the actual silica content forming in the hybrid and to evaluate the heat resistance of the hybrid. Mechanical properties such as the tensile strength and cutting strength were investigated at various concentrations of in situ silica. The tensile strength increased at all concentrations of silica. In contrast, the cutting strength decreased, probably because of a reduction of the energy dissipation from silica as physical crosslinks. The HOAc catalyzed system showed better optical properties than the HCl catalyzed system. The fracture surface was revealed through scanning electron microscopy to observe the degree of dispersion of SiO 2 , which in turn confirmed the results for the optical and mechanical properties.

Section: Introductionmentioning

confidence: 99%

Properties and preparation of thermoplastic polyurethane/silica hybrid using sol–gel process

Lai

Wang

Shen³

2005

“…Thus, networks structures with crosslinked bonds between intrachain or interchain of polyacrylonitrile (arms) are formed. The use of metal ions is similar in effect to a crosslinked agent: intermolecular friction increased and the movement of macromolecular chains of star polymer was restricted 15. On the other hand, we notice that the T g 's of the three kinds of star polymer metal complexes are different.…”

Section: Resultsmentioning

confidence: 79%

Synthesis and characterization of novel star polymer with β‐cyclodextrin core and its metal complexes

Jiang

Zhang

et al. 2007

Self Cite

A novel star polymer with b-cyclodextrin (b-CD) core and polyacrylonitrile arms and its metal complexes (Cu 2þ , Zn 2þ , and Ag þ ) were synthesized and characterized by means of infrared spectra, ultraviolet, GPC, X-ray photoelectron spectroscopy, differential scanning calorimetry, cyclic voltammetry, and electron spin resonance. The results indicate that the monomers of acrylonitrile were initiated by functionalized b-CD. The thermal properties of star polymer were improved greatly after transitional metal ions were introduced into it. The novel star polymer metal complexes possess properties of metal ions, polymer, and b-CD. Furthermore, it shows stable electrochemical activity.

“…23,24 Table II details the contact angle and surface tension data of PET film and modified PET film. The surface tensions of modified PET film (PET film/PMMA: 58.2, PET film/PAAM: 76.6, and PET film/PMMA/PAAM: 64.4) are more than that of PET film (46.0).…”

Section: Resultsmentioning

confidence: 99%

Grafting polymer from poly(ethylene terephthalate) films by surface‐initiated ATRP

Zhang

Shouro

Itoh³

et al. 2007

Self Cite

Surface-initiated atom transfer radical polymerization (ATRP) from poly(ethylene terephthalate) (PET) film was studied. Poly(methyl methacrylate) (PMMA), poly (acrylamide) (PAAM), and their diblock copolymer (PMMA/ PAAM) on the surface of PET film were successfully prepared by surface-initiated ATRP. The structures and properties of the modified PET film were characterized by FT-IR/ ATR, X-ray photoelectron spectroscopy (XPS), measurements of contact angles, and scanning electronic microscopy (SEM). The results indicate that the surface properties of PET film were greatly improved by grafted polymer.