Study on ageing characteristics and evaluation methods of RTV silicone rubber in high humidity area

Abstract

Due to high humidity, the ageing of room temperature vulcanized silicone rubber (RTV) has been a serious problem in Southwestern China. In order to solve the problem of RTV life prediction, the aging classification method was established by analyzing the microtopography of RTV samples in this paper. Besides, the comprehensive analysis of RTV element content, partial element content ratio, and major chemical groups of RTV samples in each aging level were conducted. It is found that as the ageing level increases, the element contents of C, Si, O, Al change accordingly and the ratio of C:Si drops from 2.39 to 1.54, and absorption peaks of the chemical groups of Si-(CH3)2, Si-O-Si, Si-CH3 and C-H in CH3 decrease. This work can enrich the investigation of RTV, and may provide useful reference for performance evaluation and replacement of RTV in substations.

Flexible Strain Sensor Based on Nickel Microparticles/Carbon Black Microspheres/Polydimethylsiloxane Conductive Composites for Human Motion Detection

“…The interaction of Ni/CB/PDMS, Ni, CB, and PDMS is studied by FTIR spectroscopy (Figure h). Upon embedding Ni and CB in the PDMS matrix, the peak at 2964 cm –1 corresponded to the stretching vibration of the –CH 3 group. − The characteristic peaks of Si-(CH 3 ) 2 , Si–O–Si, and Si–CH 3 in the PDMS spectrum appear at 785, 1008, and 1257 cm –1 , respectively. Significantly, the absorption peaks overlap in the Ni/CB/PDMS composites, resulting in the reduction or even disappearance of some absorption peaks.…”

Enhanced Hydrofobicity of Polymers for Personal Protective Equipment Achieved by Chemical and Physical Modification

“…The bands correspond to asymmetric stretching vibrations of the Si–O group, which confirms the structure of the main chain of the MVQ macroparticle. An intensive and sharp band of deformation vibrations at the wave number of 1258 cm −1 is typical of the Si–CH 3 group [ 47 , 48 , 49 , 50 ]. The strong and sharp band also confirms the presence of C–Si–C groups at the wavenumber of 785 cm −1 and a medium-intensity doublet in the wavenumber range between 700 and 660 cm −1 .…”

Optical Response of PDMS Surface Diffraction Gratings under Exposure to Volatile Organic Compounds

“… 53 Molecularly, the PDMS structure is helical, composed of a curved Si–O–Si chain with a layer of nonpolar methyl −CH 3 groups around the outside of the chain. 54 Thus, the most swelling of PDMS occurs in the presence of nonpolar solvents such as pentane and xylenes, where the dispersion forces are the primary contributor to the swelling parameter; polar solvents such as water and ethylene glycol causing less swelling. 53 The swelling effects of PDMS in the presence of VOCs have been used in several sensors.…”