How the hindered amines affect the microstructure and mechanical properties of nitrile-butadiene rubber composites

Meng Song,Guomin Yu,Qi Qin,Yanli Zhang,Zhongzhu Liu,Sizhu Wu,Haiyan Pei,Mingli Jiao,Xiujuan Wang

doi:10.1515/epoly-2020-0002

Abstract

Abstract Different hindered amines, GW-622 and GW-944, were added to a nitrile-butadiene rubber (NBR) matrix to prepare a hybrid damping material. The microstructure, compatibility, and dynamic mechanical properties of the hindered amine/NBR composites were investigated using Fourier transform infrared (FTIR) spectroscopy, scanning electron microscope (SEM), differential scanning calorimetry (DSC), and dynamic thermomechanical analysis (DMA). The FTIR results showed that hydrogen bonds formed between the hindered amine molecules and the NBR matrix. The SEM and DSC results showed that both GW-622 and GW-944 had partial compatibility with the NBR matrix, and a two-phase structure appeared. The effective damping temperature ranges of the hindered amine/NBR composites were narrow at room temperature and broad at higher temperatures with increasing amounts of GW-622 and GW-944. Comparatively, the damping effect from the addition of GW-944 molecules was more clearly. The present work provides a theoretical basis for the preparation of optimum damping rubber materials.

Highlights

Zhao et al studied hindered phenol AO-80/nitrile-butadiene rubber (NBR) composites, and found that organic hybrid damping materials obtained by this method have outstanding performance than compared with IPN and other methods [17]
The NBR was first plasticized on a φ152.4 mm two-roll mill at room temperature for 3 min, and GW-622 was added to the NBR with mass ratios of 0/100, 11/100, Figure 1: Molecular structures of (a) GW-622, (b) NBR and (c) GW-944. 21/100, 43/100, 64/100, and 86/100 (GW-944 was added to the NBR matrix with mass ratios of 0/100, 11/100, 22/100, 44/100, 67/100, and 89/100)
To examine the intermolecular interactions between the hindered amines and NBR rubber matrix, Fourier transform infrared (FTIR) measurements of pure hindered amines and different hindered amine/NBR composites with various mass ratios were obtained

Summary

Introduction

M. Song et al.: How the hindered amines affect the microstructure and mechanical properties 9 to have pioneered a new concept for the preparation of high-performance damping materials. Zhao et al studied hindered phenol AO-80/nitrile-butadiene rubber (NBR) composites, and found that organic hybrid damping materials obtained by this method have outstanding performance than compared with IPN and other methods [17]. NBR was selected as a substrate material for organic hybridization because of its good damping properties. Two kinds of hindered amines with different numbers of polar functional groups and steric hindrance were added to the same rubber substrate. Dynamic thermomechanical analysis (DMA) was used to study the damping properties of the two hybrid systems. The goal is to form strong hydrogen bond between hindered amines and NBR to improve the damping properties of the material

Materials

Characterization

Results and discussion