Progress ReportCOMPETABILITY BEHAVIOUR OF BINARY SOLUTION BLEND OF ELASTOMER BY ULTRASONIC & VISCOSITY TECHNIQUES

Introduction

Polymeric Blends present one of the most rapidly growing areas in polymeric materials. These materials are mixture of two structurally different polymers bonded together by secondary force [1]. However, the gain in newer properties depends on the degree of compatibility or miscibility of the polymer at molecular level. Thus the compatibility is the fundamental property in polymer blend deciding their practical utility.

Many experimental and theoretical methods have been used to investigate polymer compatibility [2, 3]. The determination of glass transition temperature, morphology by scanning electron microscopy and atomic force microscopy and dynamic mechanical response or some of the method extensively cited in the literature [4-7]. Hourston and Hughes [8] and Kaleznev et al. [9] have indicated the use of sonic and melt viscosity measurement for compatibility determination. Singh et al. [10] and Singh and Singh [11] have measured the ultrasonic velocity and absolute viscosity in solution of compatible, incompatible and semicompatible blends.

Abstract The present investigations deal with the study of compatibility behavior of bromo isobutylene-co-isoprene/bromo butyl rubber (BIIR) and acryonitrile-co-butadiene (NBR) blends. Ultrasonic velocity, absolute viscosity and density measurements have been performed on solution blends of BIIR and NBR in various blend ratios with and without addition of chlorinated polyethylene (CM) compatibilizer. The ultrasonic velocity has been observed to deviate from linearity with variation in the blend ratio without the compatibilizer. The addition of compatibilizer, however, results in a marked increase of the ultrasonic velocity and it varies linearily with blend composition. Temperature and solid content of solution blends have significant effect on the relative ultrasonic velocity and absolute viscosity. Absolute viscosity vs. blend ratio and density vs. blend ratio plots follow the same trend as observed in ultrasonic velocity vs. blend ratio plot. Morphological studies have been performed with the aid of scanning electron microscopy (SEM) & Thermal studies of Glass Transition Temperature (Tg) by Differential Scanning Calorimeter (DSC) .Keywords: BIIR, NBR, compatibility, ultrasonic velocity, scanning electron microscopy, DSC

Objectives of the Research Work In this work, it was aimed to study compatibility behavior of binary solution blends comprising of bromo butyl (BIIR) / acrylonitrile-co-butadiene (NBR)and Natural Rubber(NR)/ Styrene-butadiene rubber (SBR) elastomers because they have enormous application potential, using various analytical techniques such as ultrasonic Interferometry, viscometry, SEM and DSC. In view of the above, it has been considered worthwhile to evolve suitable compatibilizers such as chlorinated polyethylene (CPE).

.Raw Material NBR rubber was obtained from M/s. Japan Synthetic Rubber, grade JSR 220 having acrylonitrile content of 38%.

Bromo butyl rubber was obtained from Polysar, Canada, grade X2. Bromo butyl is produced by reacting bromine with butyl rubber.

Styrene Butadiene Rubber SBR rubber, grade 1502 from M/s Korean Synthetic rubber, South Korea

Natural Rubber (NR) grade

CPE was obtained from M/s. Dow Chemical, Plaquemine, LA, USA, grade Tyrin CPE 135A having chlorine content 36 mol%.

Future Uses

In future work the efficacy of suitable compatibilizer can also be established for binary solid blends of NBR-IIR and NR-SBR with the help of modern analytical techniques.Binary NBR-IIR and NR-SBR blends may have enormous applications in civil as well as defence sectors.

The solid blend of NBR-IIR may replace NBR-EPDM blend from the cast point of view.NBR-IIR rubber sheet can be used in various defence products like missiles, tanks, aircrafts etc.NR-SBR blends may have greater utility in automobile and tyre industry at lesser cost.

Formulation table for Blend NBR- IIR

With & without compatibilizer

NBRIIR10009010802070306040505040603070208010900100

Formulation table for Blend NR- SBR

With & without compatibilizer

NRSBR10009010802070306040505040603070208010900100

Compatibiliser Chlorinated Polyethylene (CPE) is added in 10 wt % of nonpolar polymer wt (IIR & SBR ) in both the matrix.2 % & 8 % rubber concentration is used in solvent (Toluene) for analysis.Same process with compatibilizer.

Test method & Characterization

Ultrasonic Velocity

Viscosity

Density

Adiabatic Compressibility

SEM

DSC

References K. Sole, Polymer Compatibility and Incompatibility, MMIPress, Harwood Academic Publishers, Chur, Switzerland, (1982).P. Mukhopadhyay and C.K. Das, Plast. Rubber Proc. Appln., 9, 141 (1988).P. Ramesh and S.K. De, Rubber Chem. Technol., 65, 24 (1992).A.Y. Koran, Rubber Chem. Technol., 63, 599 (1990).

] Pandey K.N., Setua D.K., Mathur G.N., Polym. Engg. Sci. (2005); 45 :1265-1276.

Singh K., Pandey K.N., Debnath K.K., Pal R.S. and Setua D.K.,Bull, Mater.Sci., (1996) ;19: 587-600.Setua D.K., Soman C., Bhowmick A.K., and Mathur G.N., Polym. Engg. Sci., (2002); 42:10-] Setua D.K., Pandey K.N., Sexsena A.K., and Mathur G.N., J. Appl. Polym. Sci., (1999); 74: 480-489.Pandey K.N., Debnath K.K., P.T., Rajagopalan, Setua D.K. and Mathur G.N., J. Them. Anal. Cal., (1997); 49: 281-292Singh Y.P., Das S., Maiti S. and Singh R.P., J. Pure, Appl. Ultrason(1981); 3: 1 Singh Y.P. and Singh R.P., Eur. Polym., J. (1983);19: 529-533.

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