Lewis acid is the most common compound used to initiate cationic polymerization. The more popular Lewis acids are SnCl4, AlCl3, BF3 and TiCl4. The counterion produced by the initiator-co-initiator complex is less nucleophilic than the Bronsted acid A-counterion.

Which catalyst is used for cationic polymerization?

Lewis acid catalyst Commonly used to initiate cationic polymerization by activating the oxetane epoxide, allowing nucleophilic attack and ring opening of the epoxide atom from the second oxetane molecule.

Which of the following is a common cationic polymerization initiator?

SnCl4​​​

What is a polymerization initiator?

sponsor, The source of any chemical that reacts with the monomer (A single molecule that can form a chemical bond) forms an intermediate compound, which can be connected with a large number of other monomers in turn to form a polymer compound.

Which of the following can be used as a catalyst for cationic polymerization?

Which of the following can be used as a catalyst for anionic polymerization? explain: Basic compounds such as amides, aryls, alkoxides, and Grignard reagents (R-MgX) Used as a catalyst for anionic polymerization. 7.

Cationic polymerization

24 related questions found

What is a cationic initiator?

In chemistry, cationic polymerization is a chain-extending polymerization in which a cationic initiator Transfers the charge to the monomer, which then becomes reactive. This reactive monomer continues to react similarly with other monomers to form polymers.

What are cationic polymers used for?

Cationic polymers are used for Making bioactive coatings that kill bacteria No chemicals are released from the cationic molecules themselves on contact.

What is the difference between initiator and catalyst?

Initiators initiate chemical reactions.They are not really catalysts because they become part of the final product; therefore, they are considered co-reactant. Reaction accelerators are catalysts that accelerate the progress of chemical reactions.

What is starter efficiency?

The initiator efficiency f is defined as Fraction of primary (initiator-derived) radical species added to monomer molecules. Data reported refer to ideal CSTR mixing conditions.

Who is the initiator?

Initiator is whoever started it, whatever it is. The guy yelling « Let’s start this party! » is the initiator. An initiator is an instigator, a person who starts something. Initiator comes from the Latin initiare, which means « to begin ». The spark that ignites the fuse is the initiator of the bomb explosion.

What are the two main classes of polymers?

Polymers fall into two categories:

• Thermoset or thermoset plastic.
• Thermoformed plastic or thermoplastic.

What are cationic surfactants?

What are cationic surfactants? Surfactants are substances that reduce the surface tension of a liquid or the interfacial tension of two phases.Cationic surfactants are surfactants Has a positively charged functional group. Like any surfactant, cationic surfactants are composed of polar and non-polar parts.

Which of the following is a cationic monomer?

Which of the following monomers is the most reactive for cationic polymerization? Vinyl ether>isobutylene>isoprene>styrene.

What does cation mean?

cation. (kăt′ī′ən) An ion or group of ions that have a positive charge and characteristically move towards the negative electrode during electrolysis.

Which protonic acid is not suitable for cationic polymerization?

1.5 Influence of Solvent Polarity and Temperature

Alcohols, Esters and Ketones Not good solvents for cationic polymerization as they react with growing carbocations and/or Lewis acids and quench polymerization.

What is a cationic detergent?

Cationic detergents are Amine quaternary ammonium salts with acetate, chloride or bromide as anion. They have cations at the soluble end of the chain. Cations are long chain hydrocarbons that are positively charged on the N atom. For example: cetyltrimethylammonium bromide.

Why is polymerization exothermic?

The polymerization reaction is exothermic, which means that they generate heat. Ideally, the total heat generated is small and dissipated harmlessly into the reaction vessel. However, if a large amount of monomer is present and the reaction is strongly exothermic, the monomers may combine too quickly.

What are the different types of aggregates?

There are two general types of polymerization reactions: polyaddition and polycondensation. In addition polymerization, the monomers are added to each other in such a way that the polymer contains all the atoms of the starting monomer.

What monomers are commonly used in polyaddition reactions?

Unsaturated monomers (monomers with double or triple bonds) Usually used for addition polymerization.

What is the role of initiators and catalysts?

Initiators, catalysts and inhibitors are Crosslinking process for initiating and controlling curing thermoset resins. Initiators, commonly referred to as catalysts, are used in the curing (molecular cross-linking) process of production and thermosetting resins.

What is a chemical catalyst?

catalysts, chemistry, Any substance that increases the rate of a reaction without being consumed by itself.Enzymes are naturally occurring catalysts responsible for many important biochemical reactions. …the catalyst is regenerated during the reaction between chemical intermediates and reactants.

Is polyacrylamide cationic?

Polyacrylamide (PAM) is a Commercially relevant cationic polymers Due to its high efficiency and rapid dissolution, it is mainly used in water treatment.

What is a cationic flocculant?

Cationic cellulose flocculants, keep positively charged groups, which is the basis for neutralizing negatively charged suspended dye molecules. Furthermore, since polymer chains with moderate charge densities are relatively long, bridging between particles would be a complementary mechanism.

What are cationic dyes?

Cationic dyes are Dyes that dissociate into positively charged ions in aqueous solution. They can interact with negative groups on fiber molecules to form salts, and the salts can further attach firmly to the fibers, thereby dyeing the fibers.

Which initiator is used in anionic polymerization?

The most commercially available of these initiators are Alkyl Lithium Initiator. They are mainly used in the polymerization of styrene and dienes. Monomers activated by strongly electronegative groups can even be initiated by weak anions or neutral nucleophiles (ie, amines, phosphines).