𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Benzothiazole-accelerated sulfur vulcanization. IV. Effect of ZnO and bis(2-mercaptobenzothiazole)zinc(II) on 2-bisbenzothiazole-2,2′-polysulfide formation in 2-bisbenzothiazole-2,2′-disulfide and 2-bisbenzothiazole-2,2-disulfide/sulfur

✍ Scribed by B. Morgan; W. J. McGill

Publisher
John Wiley and Sons
Year
2000
Tongue
English
Weight
167 KB
Volume
76
Category
Article
ISSN
0021-8995

No coin nor oath required. For personal study only.

✦ Synopsis

The effect of ZnO and bis(2-mercaptobenzothiazole)zinc(II) [Zn(mbt) 2 ] on 2-bisbenzothiazole-2,2Ј-polysulfide (MBTP) formation in 2-bisbenzothiazole-2,2Ј-disulfide (MBTS) and MBTS/sulfur, in the absence of rubber, was studied by heating mixes isothermally for various times and analyzing products by HPLC. Both compounds accelerate MBTP formation but do not affect equilibrium concentrations. It is proposed that ZnO induces opening of the sulfur ring, permitting more rapid sulfuration of benzothiazole radicals (BtS), while with Zn(mbt) 2 , exchange between sulfurated Zn(mbt) 2 and BtS radicals promotes their sulfuration. MBTP of lower sulfur rank form first and in the highest concentrations, while MBTP of higher sulfur rank form sequentially and form from MBTP of immediately lower sulfur rank. The concentrations of MBTP of lower sulfur rank pass through a maximum before equilibrating at lower concentrations. Reaction mechanisms to account for MBTP formation and the role of ZnO and Zn(mbt) 2 in accelerating the reactions are proposed.

📜 SIMILAR VOLUMES

Benzothiazole-accelerated sulfur vulcani
Benzothiazole-accelerated sulfur vulcanization. V. 2-Bisbenzothiazole-2,2′-disulfide/ZnO and 2-bisbenzothiazole-2,2′-disulfide/ (2-mercaptobenzothiazole)zinc(II) as accelerators for 2,3-dimethyl-2-butene
✍ B. Morgan; W. J. McGill 📂 Article 📅 2000 🏛 John Wiley and Sons 🌐 English ⚖ 175 KB

2-Bisbenzothiazole-2,2Ј-disulfide (MBTS)-accelerated sulfur vulcanization in the presence of ZnO and bis(2-mercaptobenzothiazole)zinc(II) [Zn(mbt) 2 ] was studied using 2,3-dimethyl-2-butene (TME) as a model for polyisoprene. Reactions were carried out in sealed tubes at 150°C and residual curatives

Benzothiazole-accelerated sulfur vulcani
Benzothiazole-accelerated sulfur vulcanization. III. 2-Bisbenzothiazole-2,2′-disulfide as accelerator for 2,3-dimethyl-2-butene
✍ B. Morgan; W. J. McGill 📂 Article 📅 2000 🏛 John Wiley and Sons 🌐 English ⚖ 208 KB

2-Bisbenzothiazole-2,2Ј-disulfide (MBTS)-accelerated sulfur vulcanization, in the absence of ZnO, was studied using 2,3-dimethyl-2-butene (TME) as a model for polyisoprene. Reactions were carried out in sealed tubes at 150°C and the residual curatives, intermediates, and products were analyzed by HP

Effect of carboxylic acids on 2-bisbenzo
Effect of carboxylic acids on 2-bisbenzothiazole-2,2′-disulfide- and tetramethylthiuram disulfide-accelerated sulfur vulcanization. IV. Vulcanization of polyisoprene compounds with ZnO
✍ W. J. McGill; S. R. Shelver 📂 Article 📅 1999 🏛 John Wiley and Sons 🌐 English ⚖ 219 KB 👁 1 views

The effect of benzoic and stearic acids on 2-bisbenzothiazole-2,2Ј-disulfide (MBTS)-and tetramethylthiuram disulfide (TMTD)-accelerated sulfur vulcanization of polyisoprene compounds, containing ZnO, was studied at 150°C. In the presence of ZnO, the acids are rapidly converted to their zinc salts th

Effect of carboxylic acids on 2-bisbenzo
Effect of carboxylic acids on 2-bisbenzothiazole-2,2′-disulfide- and tetramethylthiuram disulfide-accelerated sulfur vulcanization. II. Vulcanization of polyisoprene in the absence of ZnO
✍ W. J. McGill; S. R. Shelver 📂 Article 📅 1999 🏛 John Wiley and Sons 🌐 English ⚖ 180 KB 👁 2 views

Polyisoprene was vulcanized by 2-bisbenzothiazole-2,2Ј-disulfide (MBTS)/ sulfur and tetramethylthiuram disulfide (TMTD)/sulfur in the absence and presence of benzoic and stearic acids. It was found that the crosslink density of MBTS vulcanizates is halved by the addition of carboxylic acids and this

Effect of carboxylic acids on 2-bisbenzo
Effect of carboxylic acids on 2-bisbenzothiazole-2,2′- disulfide- and tetramethylthiuram disulfide-accelerated sulfur vulcanization. I. Reaction between the acids and accelerators
✍ W. J. McGill; S. R. Shelver 📂 Article 📅 1999 🏛 John Wiley and Sons 🌐 English ⚖ 172 KB 👁 2 views

Benzoic and stearic acids are shown to react with 2-bisbenzothiazole-2,2Јdisulfide (MBTS) and its polysulfides (MBTP) at vulcanization temperatures to form acid-accelerator complexes 2-benzoylthiobenzothiazole (BzM) and stearicthiobenzothiazole (StM), respectively. At higher temperatures MBTS, MBTP,

Effect of carboxylic acids on 2-bisbenzo
Effect of carboxylic acids on 2-bisbenzothiazole-2,2′-disulfide- and tetramethylthiuram disulfide-accelerated sulfur vulcanization. III. Reaction between accelerators and zinc salts of the acids
✍ W. J. McGill; S. R. Shelver 📂 Article 📅 1999 🏛 John Wiley and Sons 🌐 English ⚖ 183 KB 👁 2 views

Stearic and benzoic acids were heated with 2-bisbenzothiazole-2,2Ј-disulfide (MBTS)/sulfur/ZnO and tetramethylthiuram disulfide (TMTD)/sulfur/ZnO isothermally at 150°C and in a DSC at 2.5°C/min, in the absence of rubber. The acids readily reacted with ZnO, and at vulcanization temperatures, little o