Diphenyl Guanidine DPG

DPG is the most commonly used member of the guanidine class of rubber accelerators. DPG is commonly used as a secondary accelerator (or kicker ) with primary sulfenamide accelerators and sometimes with thiazole accelerators as well. DPG is also a silanization accelerator. It can interact with the silica surface, which then reacts with organosilanes in tread stocks to help reduce rolling resistance. DPG is not as chemically active as the thiuram or dithiocarbamate accelerators. 

Sometimes DPG has been used as the primary accelerator. Its cure profiles as a single accelerator are usually deficient in scorch safety but also slower in cure rate, compared to some other primary accelerators such as sulfonamides. 

A negative aspect of DPG is that it is toxic, and the industry is looking for DPG alternatives. 

Zhengzhou Double Vigour Chemical Product Co., Ltd. Dongying Bochen Chemical CLP PVI Co., Ltd. 

Shandong Zouping Kaiyuan Chemical Stone Material Co. United Rubber Chemical Corp. (Beijing, China) 

---

Reduction of the adhesion level will occur if certain compounding ingredients are not avoided. The acceleration system has a direct effect on the adhesion level dibenzothiazole disulphide (MBTS) gives the highest adhesion levels. If a second accelerator is used, e g., tetramethyl thiuram disulphide (TMTD) or diphenyl guanidine (DPG), then the adhesion is significantly affected. Other ingredients which cause problems are plasticisers and process oils. 

Guanidines Diphenyl guanidine (DPG) >=< C=NH Medium-speed accelerator Now largely used in conjunction with other accelerators. Strong synergism with MBT... 

Figure 10.49 Diphenyl guanidine (DPG) is produced by a chemical reaction between aniline and the highly toxic cyanogen chloride...

---