Polyether Amine-modified Nano-SiO₂and Its Application In PVA

Organic-inorganic nanocomposites is one of the key research topics of modernmaterials science. Because nano materials not only can improve the performance ofpolymer, but also because of the unique nano-effects of nanoparticles,nanocomposites will introduce some new features. But the surface functionalizationof nanoparticles, in the presence of solvent-free, basically characterized by solidbehavior.This article describes SiO2nanocomposites with liquid properties and reviewof its synthesis, and its performance in terms of the PVA films were explored.A series of silica nanoscale materials (NIMs) were prepared through a facileacid-base neutralization. These silica derivative consisted of a nanosilica core, acharged corana(sulfonic acid SIT) attatched to the core, and an oppositely chargedcanopy (PEG-substituted tertiary amines) to balance the corona. These solvent-freesilica derivative shows good flowability at room temperature. FTIR and TG indicatedthat PEG-substituted tertiary amines successfully graft into silica surface. DSC resultsindicated the melting temperature and crystallization temperature of the derivativewere slightly lower than pure PEG-substituted tertiary amines. Rheological analysisshowed that the SiO2added into the polyether amine has played a role in thethickening of the higher initial viscosity and modulus than pure polyether amines.pH=6.5AC1830-SiO2loss modulus and storage modulus of crossing pointtemperature is higher8℃than pure polyether amineNext, Prepareing PVA with SiO2nano ionic materials by mechanical mixing, getdifferent content of SiO2/PVA films and explore the films’ mechanical properties,thermal properties, dielectric properties, dispersion, crystalline properties. From theresearch, the SiO2/PVA film has good dispersibility when the particle content is low.Studying the mechanical properties of the film, found its tensile strength improves alot. When the content of SiO2is2%, the tensile strength increased by more than68.7%. Through the DMA test, glass transition temperature is3℃higher than thepure PVA film, loss modulus and loss factor are increased, and with different testfrequency, modulus and glass transition temperature of the film have different degreesof changes. With the frequency increasing, loss factor peak moved to hightemperature direction; The permittivity of blend film has been significantly improved when the content of SiO2Addition. The PVA film in the low frequency range withhigh dielectric constant and low dielectric loss, showing good dielectric properties.By studying the performance of film’s crystalline, we can found that crystallineproperties of film decreased first and then increased when the content of SiO2Addition, the relative crystallinity of film under different cooling rate is slightlydifferent. When the cooling rate is greater, the crystallization peak moves to lowertemperature, the crystallization rate is accelerated. SEM showed that modified SiO2iswell dispersed in the polymer. However, with increasing particle content reachesabout10%, particle agglomeration occurs.