Chemical properties of methyl methacrylate

Chemical properties of methyl methacrylate: ① Addition reaction with double bonds: Methyl methacrylate molecules contain carbon carbon double bonds, which enable it to undergo addition reactions. For example, under suitable catalyst conditions, it can undergo addition with hydrogen gas, causing one bond in the carbon carbon double bond to break and two hydrogen atoms to be added to the two carbon atoms of the double bond, resulting in the formation of methyl methacrylate. This reaction demonstrates the addition activity of double bonds to hydrogen, and in organic synthesis, this reaction can be used to adjust and modify the molecular structure. ② Aggregation reaction: Methyl methacrylate is prone to polymerization reaction. Under the action of initiators such as peroxides, numerous methyl methacrylate molecules can be connected to each other through carbon carbon double bonds to form long-chain polymers. The common organic glass in daily life is polymethyl methacrylate (PMMA), which is polymerized from methyl methacrylate. During the polymerization process, molecules are continuously connected through double bond addition, forming polymers with excellent optical and mechanical properties. ③ Hydrolysis reaction of esters: As an ester, methyl methacrylate can undergo hydrolysis reaction under acidic or alkaline conditions. Under acidic conditions, such as the catalytic action of dilute sulfuric acid, hydrolysis occurs to produce methacrylic acid and methanol. The reaction is slow and the hydrolysis is incomplete, but it can be considered a reversible reaction. Under alkaline conditions, such as heating with sodium hydroxide solution, hydrolysis will be more thorough, producing sodium methacrylate and methanol. By utilizing this property, the corresponding raw materials can be recovered by hydrolyzing methyl methacrylate. ④ Ester exchange reaction with alcohols: It can undergo ester exchange reaction with other alcohols. Taking ethanol as an example, in the presence of a suitable catalyst, the methyl ester group in methyl methacrylate molecules will exchange with ethanol to generate new esters - ethyl methacrylate and methanol. By selecting different alcohols, various methacrylate compounds with different ester based structures can be prepared.

⑤ Oxidation reaction: The double bond portion can be oxidized by some oxidants. For example, under mild oxidation conditions, when reacting with dilute potassium permanganate solution, the carbon carbon double bond will undergo partial oxidation, producing compounds containing hydroxyl or carbonyl groups. When encountering stronger oxidants, molecules may be deeply oxidized, and even under appropriate conditions, the entire double bond structure may be disrupted, leading to significant changes in the molecular structure.
⑥ Addition reaction with hydrogen halides: Methyl methacrylate can undergo addition reaction with hydrogen halides (such as hydrogen chloride, hydrogen bromide, etc.). When adding hydrogen chloride, the Markovnikov rule is followed, which means that hydrogen atoms will be added to the double bond carbon atoms with more hydrogen, and chlorine atoms will be added to the double bond carbon atoms with less hydrogen, generating corresponding halogenated ester compounds. This reaction can be used to introduce halogen atoms into molecules for the convenience of subsequent organic synthesis reactions.
⑦ Reaction with nucleophilic reagents: Due to the presence of ester carbonyl groups, methyl methacrylate can react with some nucleophilic reagents. For example, when reacting with ammonia or amine compounds, an ammonolysis reaction occurs, in which the nitrogen atom in ammonia or amine acts as a nucleophile to attack the ester carbonyl carbon, resulting in a series of changes and the formation of corresponding amide compounds and methanol.
⑧ Thermal stability related reactions: At higher temperatures, methyl methacrylate may undergo decomposition reactions. When heated to a certain degree, the chemical bonds within the molecule break, and it may decompose again to produce some small molecules such as methacrylic acid, carbon monoxide, carbon dioxide, etc. However, the exact decomposition products and ratios depend on factors such as the specific heating temperature, time, and reaction environment.
⑨ Photochemical reaction: Under light conditions, methyl methacrylate undergoes some special reactions. For example, it can undergo intramolecular rearrangement reactions or photo induced addition reactions with other molecules under appropriate wavelength of light. The addition of certain special photosensitizers may also alter the reaction pathway and product distribution.
⑩ Isomerization under acid-base catalysis: Methyl methacrylate molecules may undergo isomerization reactions under the catalytic action of acid or base. Under specific conditions, the double bond position may shift, forming isomers with different structures. For example, under the action of a mild acidic catalyst, changes in the position of double bonds may affect the chemical and physical properties of the molecule.

⑪ Reaction with metal organic reagents: It can react with some metal organic reagents, such as Grignard reagents. The carbon negative ion in Grignard reagent acts as a nucleophile to attack the ester carbonyl carbon of methyl methacrylate. After hydrolysis treatment, a series of complex organic compounds can be synthesized, which have important applications in organic synthesis chemistry.
⑫ Co polymerization reaction: Methyl methacrylate can undergo co polymerization reaction with other monomers with double bonds. For example, in copolymerization with styrene, two monomer units are alternately or irregularly arranged in the polymer chain during the polymerization process. This copolymer has new performance characteristics, combining the advantages of two monomer polymers, and can be used to manufacture various materials for special purposes.