Unsaturated Polyester Resin (UPR) curing agent ：Organic Peroxide 

Unsaturated Polyester Resin (UPR) is a liquid thermosetting polymer that once cured , cross-links into a rigid, durable plastic with lightweight, corrosion-resistant, and structurally strong characters. UPR composites are found in marine,Automotive, kitchen and bath, structural adhesives and engineered stone countertops etc. 

UPR are cured by free radicals which are formed when organic peroxides decompose. The decomposition initiates a reaction by which unsaturated polyester molecules polymerize with styrene forming a three dimensional network .

Organic peroxide are essential ingredients to make composites for a range of manufacturing processes such as SMC, BMC, pultrusion, resin transfer molding, spray up, artificial solid surface, etc.

To ensure optimal curing of unsaturated polyester resin (UPR), choosing the right peroxide initiator is essential. The correct selection of peroxides not only controls the reaction rate but also guarantees a complete curing process. Organic peroxides are particularly effective due to their low activation energy and the ease of controlling reaction temperatures. However, it's important to consider factors like half-life, critical temperature, and peroxide type, as they can impact the efficiency and overall quality of the curing process.

Common Organic Peroxides Used in Unsaturated Polyester Resin (UPR)  :