In order to improve dispersiveness of nanosilica in polymer matrix, surface organo-modification of nanosilica is necessary. This work reveals silica nanoparticles modified by titanate coupling agent isopropyltri (dioctylphosphate) titanate (KR12) in toluene solvent. Effect of reaction temperature, reaction time and reactant ratio on grafting efficiency have been studied by Thermogravimetric Analysis (TGA). The obtained results exhibit the grafted percentage of titanate coupling agent KR-12 on the surface of nanosilica increased quickly from 4.97 to 13.11 wt.% as increasing the content of KR-12 from 5 to 15 wt.% and raise slower from 13.21 to 13.43 wt.% as content of KR-12 in the range of 30 to 45 wt.%, respectively. The KR-12 content and grafting reaction time affect significantly on the grafting efficiency while temperature of grafting reaction is negative to the grafting efficiency. The results of analysis related to Infrared Spectroscopy and Energy-Dispersive X-ray spectroscopy (EDS) displayed titanate coupling agent KR-12 have been covalently bonded to surface of the nanosilica. The Transmission Electron Microscopy (TEM) images and size distribution indicated that after organic modification, nanosilica particles had average size about 86 nm and the agglomeration of nanoparticles decreased significantly. The obtained results showed that surface treatment of nanosilica with titanate coupling agent KR-12 was successful.

This study presents the qualitative and quantitative analyses of Fourier Transform Infrared (FTIR) spectra of poly(methyl methacrylate)/poly(vinyl chloride) blends (PMMA/PVC), as well as PVC-g-PMMA graft copolymers. Graft copolymerizations of methyl mathacrylate (MMA) onto PVC macromolecules were carried out mixture of cyclohexanone/N,N-dimethylformamide as solvents, dibenzoyl peroxide as initiator and nitrogen medium. FTIR spectra of PMMA/PVC blends showed that there were molecular interactions between C=O groups of PMMA and C-Cl groups of PVC. Assignments of infrared absorption bands for specific groups of PMMA/PVC blends have been contributed. Using regression method, linear calibration curve between PMMA mole content and peak areas of C=O groups in FTIR spectra of the blends has been found when C=O peak areas were multiplied by an appropriate factor. PMMA grafted content and total PMMA formed content in PVC-g-PMMA graft copolymers have been evaluated. The results showed that grafted PMMA content was increased since PVC was initiatly dechlorinated by NaOH solution. The grafted PMMA content and total formed PMMA content were 5.05 wt.% and 11.25 wt.% respectively when MMA monomers were grafted onto neat PVC and modified PVC molecules.

In this study, a novel recyclable, hydrophobicity foam with excellent oil/water separation based on polyurethane (PU) and polypropylene glycol (PPG) grafted stearic acid (PGGA) has been developed. PGGA was simply synthesized by the esterification of stearic acid and PPG, while the PU/PGGA foam was fabricated by the reaction of PPG and methyl diphenyl diisocynate (MDI) with the addition of PGGA. The PU/PGGA foam exhibits improved oil adsorption capacity, water rejection as well as oil/water selectivity with the increase of PGGA weight loadings. The presence of PGGA at high loading (≥ 5 wt.%) reduces the pore size and porosity of PU/PGGA foam due to the high viscosity of PGGA preventing the foam formation reaction. As a result, the oil adsorption capacity of PU/PGGA foam is slightly neglected, nevertheless, the oil/water selectivity is significantly enhanced compared to the original PU foam. The result in this work suggests a simple and cost-effective method with potential in oil removal at large scale application.

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Electrolyte films based on poly(methyl methacrylate) (PMMA), poly(vinyl chloride) (PVC) were prepared by using casting method with the addition 100 wt.% to 240 wt.% of dioctyl phthalate (DOP), propylene carbonate (PC) as plasticizers and Mg(ClO4)2 as an electrolytic salt. The Fourier infrared spectra (FTIR), tensile, electrical properties, surface morphology of electrolyte films were investigated. The FTIR spectra of plasticized PMMA/PVC blends indicated that there were secondary interactions between plasticizers and PMMA/PVC matrix. There were also molecular interactions between Mg(ClO4)2 and the blends, which indicated that Mg(ClO4)2 was well dissolved and solvated in the blends. Tensile results showed that Mg(ClO4)2 improved the elongation at break and the reduced tensile strength and Young’s modulus of the blends due to this salt can act as an internal lubricant for the blends. The SEM and EDX-mapping micrographs showed the wrinkled surface morphology of the electrolyte film, all raw materials were dispersed regularly into each others at molecular and ionic levels. For the electrolytes containing 10 wt.% of Mg(ClO4)2, the ionic conductivity increased with increasing plasticizer content and achieved in the range of 1.80 × 10-4 - 1.03 × 10-3 (S/cm). For the electrolyte containing 200 wt.% of the plasticizer, the ionic conductivity increased with increasing magnesium salt content and achieved in the range of 2.31 × 10-4 - 4.57 × 10-3 (S/cm).

This paper focuses to study on change of some characteristics of high density polyethylene (HDPE) pipes testing in Nghe An province seawater. The investigated characteristics of HDPE pipe before and after testing are structural, morphological, crystal, thermal property and stability. Infrared (IR) spectroscopy, scanning electron microscope (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and differential thermal analysis (DTA) methods were used to evaluate the change in characteristics of PE pipes after 10 testing months in Nghe An province seawater. In addition, the change in weight and tensile properties of PE pipes after testing was also investigated. The obtained results showed that the Nghe An province seawater had an influence on the structural, morphological, tensile, crystal and thermal characteristics of PE pipes.

This paper presents the effect of processing conditions on properties and morphology of chitosan particles loading lovastatin as a model drug. The processing conditions were investigated here including solvents for dissolution of drug, emulsifier content and temperature of drying process. Two solvents chosen to dissolve lovastatin were ethanol and dichloromethane. Polyethylene oxide used as an emulsifier with different contents for preparation of chitosan/lovastatin particles. Two methods for evaporation of water in the samples were freeze‐drying and natural air drying in convection oven. The characteristic properties and morphology of chitosan/lovastatin particles were observed, determined and evaluated by Fourier transform infrared spectra, size distribution, and scanning emission microscopy images. From the above data and images, we can find the most suitable condition for the preparation of chitosan/lovastatin particles.

We report on the coating of chitosan/lovastatin particles with a liquid solution of alginate using a 3D printing technique. The prepared particles are characterized by Scanning Electronic Microscopy, Infrared Spectroscopy, Dynamic Light Scattering, Differential Scanning Calorimetry, and Ultraviolet-Visible Spectroscopy. Characterization results reveal that the coating of alginate makes a considerable difference in the structure, morphology, size distribution and zeta potential of the chitosan/lovastatin particles, and the size of the coated particles is increased after the coating. We also demonstrate the drug release ability of the chitosan/lovastatin particles in simulated gastric fluid and controlled in simulated intestinal fluid. Drug release study reveals that the drug release profile of the coated particles varies significantly with the pH of the solution and the coating process significantly reduces the rate of release of the drug. We also report that the bioavailability of lovastatin particles can be improved by coating with the biopolymer layers.