Peroxide Initiators
Peroxide Initiators - Related Videos
10:29
Photochemical Initiation Of Radical Polymerization Reactions
0 Views •
2023
Source: David C. Powers, Tamara M. Powers, Texas A&M In this video, we will carry out the photochemically initiated polymerization of styrene to generate polystyrene, which is an important commodity plastic. We will learn the fundamentals of photochemistry and use simple photochemistry to initiate radical polymerization reactions. Specifically, in this module we will examine the photochemistry of benzoyl peroxide and its role as a photo-initiator of styrene polymerization reactions. In the...
02:33
Initiation of Translation
0 Views •
2020
Initiating translation is complex because it involves multiple molecules. Initiator tRNA, ribosomal subunits, and eukaryotic initiation factors (eIFs) are all required to assemble on the initiation codon of mRNA. This process consists of several steps that are mediated by different eIFs. First, the initiator tRNA must be selected from the pool of elongator tRNAs by eukaryotic initiation factor 2 (eIF2). The initiator tRNA (Met-tRNAi) has conserved sequence elements including modified bases at...
02:33
Initiation of Translation
0 Views •
2023
Initiating translation is complex because it involves multiple molecules. Initiator tRNA, ribosomal subunits, and eukaryotic initiation factors (eIFs) are all required to assemble on the initiation codon of mRNA. This process consists of several steps that are mediated by different eIFs. First, the initiator tRNA must be selected from the pool of elongator tRNAs by eukaryotic initiation factor 2 (eIF2). The initiator tRNA (Met-tRNAi) has conserved sequence elements including modified bases at...
01:47
Transcription Initiation
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2023
Initiation is the first step of transcription in eukaryotes. Prokaryotic RNA Polymerase (RNAP) can bind to the template DNA and start transcribing. On the other hand, transcription in eukaryotes requires additional proteins, called transcription factors, to first bind to the promoter region in the DNA template. This binding helps recruit the specific RNAP that can assemble on the DNA and start transcription. The promoters and enhancers and their accessory proteins allow tight regulation of...
02:23
Autoxidation of Ethers to Peroxides and Hydroperoxides
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2025
Ethers represent a class of chemical compounds that become more dangerous with prolonged storage because they tend to form explosive peroxides when standing in the air. Autoxidation is the spontaneous oxidation of a compound in air. In the presence of oxygen, ethers slowly oxidize to form hydroperoxides and dialkyl peroxides. If concentrated or heated, these peroxides may explode. Hence, ethers should be obtained in small quantities, kept in tightly sealed containers, and used promptly to...
FAQs
Activation occurs when heat or light cleaves the peroxide’s relatively weak oxygen-oxygen bond. This produces reactive radicals, which can attack carbon-carbon double bonds in monomers and create new chain radicals. The initiator’s chemical structure influences how readily this cleavage occurs, so different peroxide initiators can begin reactions at different rates and processing temperatures.
The decomposition rate controls how quickly radicals become available for initiation. A faster rate can accelerate the beginning of polymerization and influence conversion, while a slower rate can support processing at a different temperature or over a different reaction period. Matching decomposition behavior to the reaction conditions helps balance initiation, conversion, molecular weight, and resulting material properties.
Their effect begins with the number and timing of radicals generated during decomposition. Those radicals initiate growing chains, so the initiator’s structure and reaction conditions influence chain development and overall conversion. Because chain formation affects the polymer produced, selecting an appropriate peroxide initiator helps chemists balance molecular weight with the properties required for plastics, coatings, adhesives, or composites.
Selection depends primarily on the peroxide structure and the conditions needed for decomposition, including whether heat or light will provide activation and which processing temperature is appropriate. Chemists also consider the desired initiation rate and conversion. The choice should support the intended balance among reaction speed, molecular weight, processing requirements, and final material properties.
A general workflow involves choosing a peroxide structure suited to the monomer system and desired processing conditions, then applying heat or light to promote oxygen-oxygen bond cleavage. The resulting radicals add to monomer double bonds and establish propagating chain radicals. Chemists monitor the relationship between decomposition rate, initiation, conversion, and the targeted polymer characteristics.
They are used to start radical polymerization when producing polymeric materials such as plastics, coatings, adhesives, and composites. Their value extends beyond initiating the reaction because decomposition behavior can be selected to match processing temperatures and desired conversion. This makes them relevant when researchers need to connect reaction control with the performance requirements of a finished material.