Amino Acids Used as a Potential Alternative to Commercially Used Allergenic Sulfur Elastomer Vulcanization Accelerators

The aim of the work was to use biologically active additives, such as amino acids, as an alternative to traditional vulcanization accelerators in acrylonitrile–butadiene rubber (NBR), as well as a discussion of their role and impact on crosslink density, mechanical properties, aging resistance, and thermal stability of the vulcanizates. The studies have shown that the use of amino acids, in comparison to traditionally used accelerators such as 2‐mercaptobenzothiazole (MBT), 1,3‐diphenylguanidine (DPG), and tetramethylthiuram disulfide (TMTD), did not shorten the vulcanization time of NBR composites. However, the applied compounds positively influenced other parameters of vulcanization. Amino acids facilitated the vulcanization process by stabilizing sulfur bonds, increasing the enthalpy of the crosslinking process, and maintaining the crosslink density of the vulcanizates at an appropriate level. Vulcanizates with amino acids such as cystine, creatine, cysteine, and histidine exhibited improved mechanical durability and resistance to aging under elevated temperatures. Additionally, the use of amino acids contributed to the achievement of better dynamic properties of the vulcanizates, making them an attractive alternative in the production of high‐performance elastomeric materials.