Synthesis and characterization of phenolic resol resin blended with silica sol and PVA

Abstract

The phenolic resol resin (PF) has a wide application in industry, but its poor tensile ductility and insufficient mechanical strength have severely limited its application. To overcome these limitations, in this study, the mixtures of silica sol and poly(vinyl acohol) (PVA) were used to modify the PF. The structure, morphology, mechanical properties, and thermal stability of these hybrid materials were investigated by FTIR, SEM, tensile shear test (TSS), and TG. FTIR spectra indicated that the multiple reactive functional silanol group SiAOH on the surface of SiO 2 particles reacted with PVA and PF. Compared with pure PF, the composite 50-50-3% exhibited the maximum shear strength which increased by 158%, whereas the elongation at break increased by 63%. Morphological results agreed well with the mechanical properties. The TG results suggested that the composite material 50-50-3% and pure PF had almost the same thermal stability because silica sol and PVA had opposite effects on the heat resistance of the hybrid materials.

Tailoring adhesive forces between poly(dimethylsiloxane) and glass substrates using poly(vinyl alcohol) primers

“…Therefore, the fundamental adhesive force is determined by the PVA DH, and is weakened if the thermal treatment that enhances crystallinity by being prepared in dry conditions. The PDMS/PVA/Glass structure is similar to the SiOPVAOSi bonding structure in PVA binders for silica particles . For the silanol‐modified PVA (bottom left in Figure ), the initial chemical adsorption is also attributed to hydrogen bonding between the hydroxyl groups on the main chain and on the silanol group.…”

Synthesis, Spectral and Thermal Degradation Kinetics of the Epoxidized Resole Resin Derived from Cardanol

“…1 H NMR spectra were recorded on a Bruker DRX-300 NMR spectrophotometer (Japan) at the temperature range of −90°to +80°C. 1 H NMR spectra were recorded on a Bruker DRX-300 NMR spectrophotometer (Japan) at the temperature range of −90°to +80°C.…”

“…Fourier-transform infra-red (FTIR) spectroscopy of the prepared blend samples was performed on a "Nicollet Magna 740" spectrophotometer in the wavelength range of 4000-400 cm −1 to study the formation of various functional groups and the chemical changes that occurred when the reaction took place in the samples. 1 H NMR spectra were recorded on a Bruker DRX-300 NMR spectrophotometer (Japan) at the temperature range of −90°to +80°C. About 20 mg of sample, in a 10-mm diameter sample tube, was dissolved in about 5 mL of chloroform-d 1 (CDCl 3 ), which was used as a solvent along with trimethylsilane as an internal standard.…”

“…[1][2][3][4][5] Owing to increasing price of petrochemical products with growing environmental concerns, the use of natural renewable sources that can serve as alternative feedstock of monomer for polymer industry will be beneficial in the development of novel ecofriendly materials. These resins are used across a wide range of industries due to their application in commercial products such as electronic materials, adhesives, coatings because of their good physical and chemical properties.…”

Flame retardant and mechanical properties of phenolic foams toughened with phosphorus- and boron- containing polyethylene glycol esters

“…[4] The polymeric toughening agents, such as polyethylene glycol (PEG) and polyvinyl alcohol (PVA) are usually incorporated during the preparation of the phenolic foams to enhance their toughness. [5,6] However, the commonly used polymeric toughening agents are very flammable resulting in a decrease in flame retardancy of PF foams.…”