Description
Benzenesulphonyl hydrazide (BSH) is a chemical blowing agent used to modify the cell structure of natural rubber. The decomposition temperature of BSH blowing agent is 105 °C, and its gas release rate is 120 cm
3/g. In the preparation of natural rubber thermal insulation materials, the BSH blowing agent decomposes upon heating to produce nitrogen gas, thereby forming a foam structure within the rubber. When the BSH content is 6 phr, the maximum swelling ratio reaches 324% and the thermal conductivity reaches a minimum of 0.040 W/m/K, making the material an excellent thermal insulation material [1]. Furthermore, BSH is also used as the core material in evaporable core-shell nanocapsules to enable thermally triggered separation of thin films [2].
Chemical Properties
Benzenesulfonohydrazides,unlike the benzenesulfonamides, are thermally unstable. They decompose, when heated in water in some cases, to form sulfides, thiosulfonates, and nitrogen; for this reason they are used as blowing agents in the production of foams.
Chemical Properties
Benzenesulfonyl hydrazide is WHITE POWDER
Uses
Benzenesulfonyl hydrazide is used in making foam rubber and foam plastics.
Production Methods
Benzenesulfonyl hydrazides are produced by treating benzenesulfonyl chlorides with hydrazine in dioxane, alcohol, or water and in the presence of a second equivalent of hydrazineoranotherbase. They react with nitrous acid to form benzenesulfonyl azides according to the following equation:
ArSO
2NHNH
2 +HNO
2→RSO
2N
3 +2H
2O
General Description
Benzenesulfonyl hydrazide is a white to light-colored crystalline solid. Insoluble in water and denser than water. Contact may irritate skin, eyes and mucous membranes. May be toxic by ingestion. Readily ignited by sparks or flames and burns vigorously. Used to make other chemicals.
Air & Water Reactions
Insoluble in water.
Reactivity Profile
Self-decomposition or self-ignition may be triggered by heat, chemical reaction, friction or impact. May be ignited by heat, sparks or flames.
Safety Profile
Poison by ingestion. A
flammable solid. When heated to
decomposition it emits toxic vapors of NOx
and SOx.
References
[1] Rungtawee Padakan, Surachai R. (2016). Evaluation of benzenesulfonyl hydrazide concentration on mechanical properties, swelling and thermal conductivity of thermal insulation from natural rubber. Agriculture and Natural Resources, 50 3, Pages 220-226.
https://doi.org/10.1016/j.anres.2016.01.004[2] Yoongook Park , Jun H. L. (2020). Facile separation of optically transparent adhesive films by heat-triggered gas generation of vaporizable core–shell nanocapsules embedded with benzenesulfonyl hydrazide. Journal of Industrial and Engineering Chemistry, 90, Pages 312-318.
https://doi.org/10.1016/j.jiec.2020.07.029
