MEKP (Methyl Ethyl Ketone Peroxide) is a liquid curing agent, usually formulated as a 50% solution of dimethyl ester as the active ingredient. The quality of curing agents in the market varies, with some having drawbacks such as high content of low-molecular substances and excessive moisture. Due to frequent explosion accidents caused by inadequate production processes, many manufacturers currently avoid using distillation to remove water. Instead, they use a low-temperature cooling and static separation method. However, this method often leaves residual water in the curing agent, resulting in high moisture content. Employing multiple freezing and separation steps leads to low yield and high costs.
Some vendors aim to increase the curing agent’s active oxygen content by directly adding hydrogen peroxide. Using such curing agents may lead to the following phenomena:
1.After adding curing agents and promoters to the resin, significant bubbling occurs, particularly noticeable in resins with low reactivity or high levels of inhibitors.
2.During summer with rising temperatures, bubbling becomes more severe due to rapid decomposition of hydrogen peroxide in the curing agent, failing to react promptly with the resin.
MEKP is the most commonly used ambient temperature curing agent, typically used in conjunction with promoters. Promoters commonly include cobalt naphthenate with a 6% cobalt content or isooctoic acid cobalt with a 12% cobalt content, along with co-promoters like dimethyl aniline or diethyl aniline (DEA). Standard MEKP with an effective oxygen content of 9% is widely used, but certain resin grades may require MEKP with lower hydrogen peroxide content. Hydrogen peroxide can cause excessive bubbling in vinyl resins.
We, at Thousands Chemicals, recommend curing agents that result in high-performance vinyl resins characterized by low bubbling, more reasonable and targeted control of heat release peak temperature and heat release speed (CT-GT)/GT, better operability, extended product shelf life (up to 3-12 months), and improved stability. Contact us for more information regarding gelation time and curing heat release peak temperature data after adding curing agents to vinyl resins.
MEKP is generally a plasticizer solution of around 9% active oxygen content of methyl ethyl ketone peroxide. Different specifications of MEKP exhibit varying curing effects, mainly due to trace variations in the monomer and dimer content in different peroxides. MEKP is often used in combination with ethyl resins, proven to rapidly cure and produce stable high-performance products like Butanox LPT. Other equivalent methyl ethyl ketone peroxide products can also be used, but consulting Thousands Chemicals’ experts before actual usage is advisable.
MEKP should be stored in a sealed manner, avoiding water ingress. The presence of water significantly affects resin curing. If MEKP appears cloudy, it indicates excessive moisture content.
For optimal curing results, consult our experts before actual usage.