Vulcanizing agent DHBP is mainly used as a high-temperature vulcanizing agent for vinyl silicone rubber, and is also an excellent vulcanizing agent for other types of rubber. Rubber vulcanized with vulcanizing agent DHBP has advantages such as high tensile strength and high hardness.
This article focuses on the production process of vulcanizing agent DHBP :
1, Peroxide
1. When the acid entering the peroxide pot reaches the stirring level, start stirring. Open the inlet and outlet valves and regulating valves of the refrigerant, and select the initial flow rate of the refrigerant based on the temperature inside the kettle; After the acid solution is discharged, close the bottom valve of the acid mixing tank and adjust the temperature inside the peroxide tank to ≤ 30 ℃; Open the hexanediol screw conveyor, transport the hexanediol into the peroxide kettle, control the feeding temperature to ≤ 30 ℃, and adjust the speed according to the temperature inside the kettle. After adding, turn off the screw conveyor, and continue stirring at 30 ℃ for 45 minutes before discharging.
2. Before the insulation of the peroxide kettle is completed, adjust the centrifuge to the standby state; Open the air valve from the centrifuge to the reused acid storage tank, and when the centrifuge is in normal working condition, open the air valve at the bottom of the peroxide kettle. Put the oxidized material into a centrifuge; Centrifuge for 90 seconds. Continue to rinse the oxide in the centrifuge with clean water for 20 minutes, then rinse with baking soda solution for 10 minutes, maintain centrifugation for 90 seconds, and stop the centrifuge.
3. After the centrifuge is completely stationary, lower the mobile elevator hook, fix the hook on the centrifuge filter bag bracket, and secure it with a fly rope. Then, open the elevator and transport the qualified oxide into the designated container.
2, Tert butylation
1. When the temperature inside the esterification kettle is adjusted to below 30 ℃, open the bottom valve of the high level tank for tert butanol, put tert butanol into the esterification kettle, drain it, and close the bottom valve. Open the bottom valve of the high level tank for dilute sulfuric acid, appropriately open the regulating valve for dilute sulfuric acid dripping, and start dripping dilute sulfuric acid. The temperature control during dripping is ≤ 30 ℃, and the dripping speed is adjusted according to the temperature inside the pot.
2. After the esterification solution is qualified, open the discharge valve from the esterification kettle to the corresponding synthesis kettle, and put the esterification solution into a stainless steel reaction pot until it is completely discharged. Turn on the mixer, adjust the temperature inside the pot to below 30 ℃, and slowly add oxides. When adding oxides, pay attention to the temperature changes inside the reaction kettle. After adding, turn on the jacket warm water circulation pump (the temperature inside the hot water tank is controlled at 60 ℃), raise the temperature inside the pot to 50 ℃, and turn off the warm water circulation pump. After insulation at this temperature for 4 hours, after passing the gas chromatography test, open the cooling water inlet and outlet valve of the coil in the pot, and prepare for discharge when the temperature inside the pot drops.
3. When preparing for discharge, open the inlet and outlet valves of the condenser's frozen liquid and the stratified kettle's frozen liquid, and then slowly put the material into the stratified kettle. After the material is discharged, close the inlet and outlet valves of the condenser and stratified kettle's frozen liquid. The material remains stationary in the layering kettle for 1 hour, open the bottom valve of the layering kettle, wait for the layering mirror material to stabilize, and then layer it. The recycled acid in the lower layer is placed in the collection tank.
The above is the synthesis of DHBP, and the specific purification and acid treatment are shown in the next section.https://www.kz-opchem.com/organic-peroxides/dhbp-cas-78-63-7-2-5-dimethyl-2-5-di-tert.html