What is a polymerization reaction and is it the same as a polymerization reaction?

Such a reaction from a compound with a small relative molecular weight to an organic polymer compound with a relatively large molecular mass is called a polymerization reaction, and a polymerization reaction like ethylene to polyethylene is also called an addition polymerization reaction, referred to as a polyaddition reaction.

Polymerization is a reaction process in which polymers are synthesized from monomers. Polymerization reactions are divided into polycondensation reactions and polyaddition reactions.

Polyaddition reaction: that is, addition polymerization reaction, compounds containing unsaturated bonds (double bonds, triple bonds, conjugated double bonds) or cyclic low molecular compounds, under the action of catalysts, initiators or radiation and other external conditions, the reaction of the same monomer to form new covalently bonded macromolecules is the polyaddition reaction.

Polycondensation reaction: It is a monomer with two or more functional groups that reacts with each other to form polymer compounds, and at the same time produces simple molecules (eg.

H2O, Hx, alcohols, etc.).

The polymerization reaction is.

The reaction of the polymerization of monomers into polymers. Polymerization with only one monomer is called homopolymerization, also known as polymerization. When the monomer polymerizes to form an oligomer with a small molecular weight, it is called a low polymerization reaction, and the product is called an oligomer.

When two or more monomers polymerize together, it is called copolymerization, and the product is called copolymer. From the perspective of polymerization reaction kinetics, there are two main types of polymerization reactions, one is chain polymerization reaction, such as addition polymerization of alkene monomers, referred to as polymerization. The second is the gradual polymerization reaction, such as the condensation polymerization between difunctional acids and diamines, referred to as polycondensation.

Lactic acid (IUPAC scientific name: 2-hydroxypropanolic acid) is a chemical compound, it is a carboxylic acid, its molecular formula is C3H6O3, the structure is simplified.

ch3ch(oh)cooh

It is a carboxylic acid that contains a hydroxyl group and is therefore an alpha hydroxy acid. Because it has both carboxyl and hydroxyl groups in its molecular structure, it can be polymerized. It can undergo a polycondensation reaction to form polymer compounds.

Polymerization is to break the double or triple bonds, and the leaked bonds are connected to the original other bond (if it is the same substance), and then connected in turn.

The definition of polymerization reaction will not be repeated. According to the definition of a polymerization reaction, if a monomer polymerizes to produce an oligomer with a low molecular weight, it may not become a polymer compound (the molecular weight of a polymer is usually large). So, it's not necessarily just the monomer that becomes a polymer.

The reaction process of synthesizing polymers from monomers. The low molecular weight raw materials with polymerization ability are called monomers, and the polymerization raw materials with large molecular weights are called macromolecular monomers.

Examples of polymerization reactions:

Polycondensation – monosaccharides form polysaccharides and amino acids form proteins.

Poly - most of the rubber.

The polyaddition reaction is an addition polymerization reaction, which is generally a reaction in which compounds containing unsaturated bonds are added to each other to form new covalent bonds linked to macromolecules. For example, ethylene has unsaturated double bonds, and there are many ethylene that open this double bond and add to each other to form a large molecular polyethylene.

Polycondensation is a chemical reaction in which monomers with two or more functional groups react with each other to form polymer compounds, and at the same time produce chemical reactions with simple molecules (such as H2O, Hx, alcohol, etc.). For example, adipic acid and ethylene glycol, the carboxyl group at one end of the adipic acid is connected to the hydroxyl group at the other end of the ethylene glycol, and the hydroxyl group at the other end of the ethylene glycol is connected to the carboxyl group of the next adipic acid, and so on, can be condensed into a large molecule polyethylene glycoate.

Polyaddition and polycondensation are collectively referred to as polymerization.

The condition of the polyaddition reaction is the reaction in which the alkene monomers are polymerized by addition.

Polyaddition reaction is addition polymerization reaction, some compounds containing unsaturated bonds (double bonds, triple bonds, conjugated double bonds) or cyclic low molecular weight compounds, under the action of catalysts, initiators or radiation and other external conditions, the reaction of the same monomer to form new covalently bonded macromolecules is the polyaddition reaction.

Unsaturated bond monomers such as alkenes or alkynes react with each other to form a polymer compound, called polyaddition. After the polymerization reaction is initiated by an initiator, the monomers are added to the top of the polymerization chain one by one to form polymers.

Anion polymerization reaction:

This polymerization reaction is very similar to that of cationic polymerization. The difference is that the reaction uses a Lewis base (such as sodium ethanol, sodium diisopropylamine, sodium amino, Grignard reagent, organolithium reagent, etc.) Lewis base and a monomer reaction to produce a new Lewis base.

The new Lewis base will continue to attack the next monomer, an addition reaction occurs, and so on. The reaction is terminated by substances that can be acidic (e.g., Lewis acid, hydronium ions, etc.).

When this reaction occurs, if there are groups that are easy to leave, there is a possibility that a side reaction may occur. The side reaction is a nucleophilic substitution of hydrocarbons so that no polymerization occurs. When the carboanion is formed, the rearrangement of the carboanion may also occur, so as to form a more stable carbanion and change the carbon frame structure of the product.

a.Unsaturated to do the source of the reverence group.

b.Irreversible.

c.There are no small molecule by-pure cleavage products.

Correct answer: ABC

1. The reaction principle is different

1) Addition polymerization: that is, addition polymerization reaction, some compounds containing unsaturated bonds (double bonds, triple bonds, conjugated double bonds) or cyclic low molecular compounds, under the action of catalysts, initiators or radiation and other external conditions, the reaction of the same monomer to form a new covalent bond linked macromolecule is the addition reaction.

2) The addition reaction is a characteristic reaction of unsaturated compounds.

The addition reaction is that two atoms at the end of the reactant molecule bound by heavy bonds or conjugated unsaturated systems are bonded to groups or atoms provided by the reagent respectively in the reaction to obtain a saturated or relatively saturated addition product.

2. Different classifications:

1) The polymerization reaction mainly includes cationic polymerization, anionic polymerization, radical polymerization and metal catalyst polymerization, which are suitable for different monomers.

2) Addition reactions can be divided into ionic additions, radical additions, cycloadditions, and heterogeneous additions. The most common of these are electrophilic addition of olefins and nucleophilic addition of carbonyl groups.

Addition reaction: it is to open (break) unsaturated bonds (double bonds, triple bonds, etc.) to form connections between monomers; Polyaddition: It is to open the rings in the molecule and form a link between the monomers.

1. Polyaddition reaction: common in the synthesis of organic polymers. Generally, it is the alkene that reacts with the alkyne, and the reaction sites are double and triple bonds on the molecule. The reaction does not produce other molecules, but simply connects the molecules.

2. Addition reaction: It is an organic chemical reaction, which occurs in substances with double or triple bonds (unsaturated bonds). The reaction in which two or more molecules interact with each other to form an addition product is called an addition reaction.

Addition reactions can be ionic, radical, and synergistic.

3. In essence, addition polymerization (addition reaction) is the real opening of unsaturated bonds, such as: polymerization of ethylene and acetylene, and polymerization of butadiene. And polyaddition is not an addition at all, but a substitution reaction.

If we pay a little attention, we can find that each group of polyaddition reactions has a corresponding set of polycondensation reactions that can produce the same product, such as: ester can be acid plus alcohol dehydration, rotten reed ear can also be acid anhydride plus ether, amide can be acid plus amine dehydration, or acid anhydride plus amine. This is said to be hungry, and poly-addition can also be regarded as a "condensation reflux reaction" of early dehydration.

The polyaddition reaction can be regarded as a special case of addition reaction, addition reaction: that is, addition polymerization reaction, some compounds containing unsaturated bonds (double bonds, triple bonds, conjugated double bonds) or cyclic low molecular compounds, under the action of catalysts, initiators or radiation and other external conditions, the reaction of the same monomer to form new covalent bonds linked macromolecules is the polyaddition reaction. The addition reaction is a characteristic reaction of the class of unsaturated compounds.

The polyaddition reaction mainly includes cationic polymerization, anionic polymerization, free radical polymerization and metal catalyst polymerization, which are suitable for different monomers.

1.Cation polymerization.

The initiators used in cationic polymerization are usually strong Lewis acids (e.g., protons, phosphorus pentafluoride, etc.) or oleum. Under acidic conditions, protons or lewis acids attack monomer double bonds or rings, undergo an addition reaction, stabilize themselves and form a new lewis acid, which continues to attack the next monomer. After several repetitions of the reaction, a polymeric chain is formed (the monomers in the figure below are different, but the reaction mechanism is the same).

When the polymerization chain hits the Lewis base, the top of the carbon chain gets a coordination bond and the reaction is terminated.

2.Anion polymerization reaction:

This polymerization reaction is very similar to that of cationic polymerization. The difference is that the reaction uses a Lewis base (such as sodium ethanol, sodium diisopropylamine, sodium amino, Grignard reagent, organolithium reagent, etc.) Lewis base and a monomer reaction to produce a new Lewis base. The new Lewis base will continue to attack the next monomer, and an addition reaction occurs.

3.Free radical polymerization.

Free radical polymerization is also very similar to the above two polymerization reactions. The difference is that the reaction first mixes a polymer with a substance that can form free radicals under special conditions (this substance is called a free radical initiator). The mixture is subjected to special reaction conditions (e.g. heating, ultraviolet light, etc.) and the free radical initiators in it can generate free radicals.

Common free radical initiators include benzophenone, benzoyl peroxide, ammonium persulfate, etc.