i want to make epdm rubber sheet for making chemical diaghrams for pump using press cure.  
epdm : 2kg , neoprene : 1kg, smoke: 500gram, carbon : 500gram,
sulfur :40 gram, zinc : 100 gram, steric : 50 gram , and curing agents  e3g : 80 grams , mbts : 50 grams  i cook my mould for 25 mint on 180 cenetigrade but my finish produc turn grey. i want it should remain black not change colour.

Dear sir,

As I can conclude from your formulation, I suggest the following change:
Your level of carbon is low, and problably the particle size is high, because that it turn grey, I suggest to change it to a fine particle carbon black : N110 or N220 and the color will tend more to black.

Or on the other hand increase the level of carbon black to 30-40 phr and reduce the hardness using a plasticizer.



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Luis Antonio Tormento


Operational Chemical Engineer with specialization in rubber compounding and processing: - Vast knowledge on rubber molding techniques: extrusion, press and injection molding. - Marketing expertise on the development of applications of rubber chemicals, precipitated silica and specialty rubbers. - In his career he developed numerous production compounds for automotive and industrial hose, rubber mats, retread compounds, tire compounds, shoe soles and molded products. TPE/TPV/TPO applications


I have 36 years working in plant processing of hose, tire, shoes and press/injected cured rubber compounds and technical assistance for two big raw material suppliers: Chemtura and Nitriflex. Actually I have my own company

2006-2011 - Rubber Division Director - Brazil Rubber Group 2008-2009 - Vice President - Brazil Rubber Group 2002-2007 - President - Brazil Rubber Group 2000-2001 - Technical Director - Brazil Rubber Group

Several papers published on magazines, congress and conferences about rubber processing and compounding

Chemical Engineer by FEI - Brazil (1979) Advanced Rubber Technology - Rubber Division (1992) University Expert on Plastic and Rubber - UNED (Spain) - 2002

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