Gen­er­al-pur­pose rub­bers:
The group of gen­er­al-pur­pose rubbers

Buta­di­ene rub­ber, like styrene-buta­di­ene rub­ber, orig­i­nat­ed in the ear­ly 20th cen­tu­ry from the inten­tion to replace nat­ur­al rub­ber with a cheap, read­i­ly avail­able alter­na­tive. Unlike SBR, how­ev­er, BR is almost nev­er used in its pure form. As a rule, it serves as a blend­ing com­po­nent to improve the mechan­i­cal prop­er­ties of oth­er types of rub­ber.

BR exhibits mod­er­ate to good resis­tance to polar sol­vents and dilute acids and alka­lis. It is also char­ac­ter­ized by high rebound resilience, very good abra­sion resis­tance and low heat­ing under dynam­ic loads.

How­ev­er, buta­di­ene rub­ber is not resis­tant to non-polar and aro­mat­ic sol­vents, oils, greas­es, lubri­cants and gaso­line. Its aging tol­er­ance to (UV) light, ozone and weath­er­ing is also poor to mod­er­ate. The same applies to ten­sile strength, elon­ga­tion at break and tear resistance.

Pure BR com­pounds are dif­fi­cult to process. They have to be blend­ed with high pro­por­tions of fillers and/or plas­ti­ciz­ers. In prac­tice, there­fore, they play only a minor role.

Instead, the major­i­ty of BR pro­duc­tion goes to the tire indus­try as a blend­ing com­po­nent. The addi­tion to nat­ur­al rub­ber or styrene-buta­di­ene rub­ber improves their abra­sion and rolling resis­tance as well as elas­tic­i­ty. Oth­er appli­ca­tions for BR-rein­forced elas­tomers include con­vey­or belts, shoe soles, roll cov­ers and bear­ing elements.