25134-01-4

Basic information

• Product Name: POLY(2,6-DIMETHYL-1,4-PHENYLENE OXIDE)
• Synonyms: 2,6-dimethyl-phenohomopolymer;Phenol,2,6-dimethyl-,homopolymer;POLY(2,6-DIMETHYL-1,4-PHENYLENE OXIDE);POLY(2,6-DIMETHYLENE-P-PHENYLENE OXIDE);POLY(2,6-DIMETHYL-P-PHENYLENE OXIDE);2,6-DIMETHYL-1,4-PHENYLENE OXIDE POLYMER;POLY(2,6-DIMETHYL-1,4-PHENYLENE OXIDE), SECONDARY STANDARD;Poly(2,6-dimethyl-1,4-phenylene oxide), approx. M.W. 50,000
• CAS NO: 25134-01-4
• Molecular Formula: C8H10O
• Molecular Weight: 122.1644
• Product Categories: Polymers;Poly(phenylene oxide) Thermoplastic Resins;Engineering Polymers;Polymer Science
• Mol File: 25134-01-4.mol
• Article Data: 186

Chemical Properties

• Melting Point: 258-261 °C
• Boiling Point: 206°Cat760mmHg
• Flash Point: 101.6°C
• Appearance: /powder
• Density: 1.06 g/mL at 25 °C(lit.)
• CAS DataBase Reference: POLY(2,6-DIMETHYL-1,4-PHENYLENE OXIDE)(CAS DataBase Reference)
• NIST Chemistry Reference: POLY(2,6-DIMETHYL-1,4-PHENYLENE OXIDE)(25134-01-4)
• EPA Substance Registry System: POLY(2,6-DIMETHYL-1,4-PHENYLENE OXIDE)(25134-01-4)

Safety Data

• WGK Germany: 3
• Hazardous Substances Data: 25134-01-4(Hazardous Substances Data)

Usage

Description

Poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) is an anion exchange membrane (AEM) material that is primarily utilized as a cross-linker. It is characterized by its high tensile strength, stiffness, impact strength, and creep resistance, along with excellent dielectric properties. These attributes are preserved over a wide temperature range (approximately -45 to 120°C). PPO is a self-extinguishing polymer with a high glass-transition temperature (Tg = 208°C), which limits crystallization in standard molding processes. The polymer is also known for its good dimensional stability, having a very low coefficient of thermal expansion and low water absorption. It is soluble in aromatic hydrocarbons and chlorinated solvents, but susceptible to environmental stress cracking from certain aliphatic hydrocarbons. PPO demonstrates remarkable resistance to most aqueous reagents, remaining unaffected by acids, alkalis, and detergents.

Uses

Used in Fuel Cells:
PPO, when modified with imidazolium and combined with liquid ionic graphene oxide, is used as an anion exchange membrane (AEM) composite. This composite has a peak power density of 136 mW cm?2, making it suitable for the fabrication of high-performance fuel cells.
Used in Vanadium Redox Flow Batteries (VRFBs):
PPO can be sulfonated to form a long-chained polymeric structure with an efficiency of 81.8% at a current density of 120 mA cm?2. This structure is potentially useful in vanadium redox flow batteries (VRFBs) as an effective energy storage system.
Used in Microbial Desalination Cell Systems (MDCS):
PPO can also be utilized in the formation of anion exchange membranes (AEMs), which are employed in the development of microbial desalination cell systems (MDCS) for water treatment applications.
Used in Telecommunication and Business Equipment:
Commercially, PPO is often blended with polystyrene, primarily in the form of high-impact polystyrene, to facilitate melt-processing and lower costs while maintaining the desirable properties of the pure polymer. Polystyrene-modified poly(2,6-dimethyl-1,4-phenylene oxide), commonly referred to as PPO, is used in the manufacturing of telecommunication and business equipment housings and components.
Used in Automotive Industry:
The blend of PPO and polystyrene also finds applications in the automotive industry for the production of various automotive parts, benefiting from the combined properties of both materials.

Preparation

Oxidative coupling is readily accomplished by passing oxygen into a reaction mixture containing 2,6-xylenol, pyridine and cuprous chloride. (The molar ratio of pyridine to cuprous ion is generally in the range 10: 1 to 100: 1.) External heating is unnecessary; during the course of the reaction the temperature rises to about 70°C. The polymer is precipitated with dilute hydrochloric acid and collected by filtration. It is generally accepted that aryloxy radicals are intermediates in the polymerization reaction since ESR studies have shown the presence of both monomeric and polymeric aryloxy radicals in polymerizing solutions of 2,6- xylenol. The simplest mechanism that can be suggested for the reaction is aromatic substitution:

Upstream product

• 2816-57-1 2,6-dimethylcyclohexanone 
• 824-42-0 2-methoxy-3-methylbenzaldehyde 
• 23802-11-1 2-(dimethylamino-methyl)-6-methyl-phenol 
• 111-87-5 octanol 
• 15261-41-3 1-allyloxy-2,6-dimethylbenzene 
• 19578-74-6 1,3-Dimethyl-2-(phenylmethoxy)benzene 
• 82054-07-7 3,3,3'',3''-tetramethyl-3a',4',7',7a'-tetrahydro-dispiro[oxirane-2,1'-(4,7-methano-inden)-8',2''-oxirane] 
• 4919-37-3 3,5-dimethyl-4-hydroxybenzoic acid 
• 53012-41-2 (2,6-dimethylphenoxy)-2-propanone 
• 87-62-7 2,6-dimethylaniline 
• 67-56-1 methanol 
• 108-95-2 phenol 
• 123-75-1 pyrrolidine 
• 876-98-2 2,6-dimethylphenyl acetate 

Downstream Products

• 29237-05-6 4-(4,4'-dihydroxy-3,5,3',5'-tetramethyl-benzhydrylidene)-2,6-dimethyl-cyclohexa-2,5-dienone 
• 60211-21-4 4,2',6'-trimethyl-2,4'-methanediyl-di-phenol 
• 854669-64-0 3-chloro-1,1-bis-(4-hydroxy-3,5-dimethyl-phenyl)-butane 
• 108975-44-6 4-{[N-(2-hydroxy-ethyl)-anilino]-methyl}-2,6-dimethyl-phenol 
• 108170-13-4 2-(2,6-dimethyl-phenoxymethyl)-5-methoxy-pyran-4-one 
• 2786-80-3 4-hydroxy-3,5-dimethoxyazobenzene 
• 1778-65-0 2,6-Dimethyl-4-(4-nitro-phenylazo)-phenol 
• 43109-10-0 2,6-dimethyl-4-[(E)-(2,4-dinitrophenyl)diazenyl]phenol 
• 116130-99-5 (3-bromo-phenyl)-bis-(4-hydroxy-3,5-dimethyl-phenyl)-methane 
• 73324-22-8 1,1,1-trichloro-2,2-bis-(4-hydroxy-3,5-dimethyl-phenyl)-ethane 
• 107055-25-4 4-sec-Butyl-2,6-dimethyl-phenol 
• 102590-03-4 6,6-bis-(4-hydroxy-3,5-dimethyl-phenyl)-heptanoic acid 
• 115034-73-6 butyl-malonic acid bis-(2,6-dimethyl-phenyl ester) 
• 66232-87-9 GRI 406402 

Relevant articles and documents

ALKYLATION OF PHENOLS BY METHANOL WITHOUT CATALYST

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Phenol Alkylation with Methanol on Oxide and Zeolite Catalysts

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Catalytic Synthesis of 2,6-Dimethylphenol from Methanol and Cyclohexanone over Titanium Oxide-supported Vanadium Oxide Catalysts

2,6-Dimethylphenol has been selectively synthesised from methanol and cyclohexanone in one step over a vanadia/TiO2 catalyst.

Catalytic Activation of Unstrained C(Aryl)-C(Alkyl) Bonds in 2,2′-Methylenediphenols

Catalytic activation of unstrained and nonpolar C-C bonds remains a largely unmet challenge. Here, we describe our detailed efforts in developing a rhodium-catalyzed hydrogenolysis of unstrained C(aryl)-C(alkyl) bonds in 2,2′-methylenediphenols aided by removable directing groups. Good yields of the monophenol products are obtained with tolerating a wide range of functional groups. In addition, the reaction is scalable, and the catalyst loading can be reduced to as low as 0.5 mol %. Moreover, this method proves to be effective to cleave C(aryl)-C(alkyl) linkages in both models of phenolic resins and commercial novolacs resins. Finally, detailed experimental and computational mechanistic studies show that with C-H activation being a competitive but reversible off-cycle reaction, this transformation goes through a directed C(aryl)-C(alkyl) oxidative addition pathway.

A mild and practical method for deprotection of aryl methyl/benzyl/allyl ethers with HPPh2andtBuOK

A general method for the demethylation, debenzylation, and deallylation of aryl ethers using HPPh2andtBuOK is reported. The reaction features mild and metal-free reaction conditions, broad substrate scope, good functional group compatibility, and high chemical selectivity towards aryl ethers over aliphatic structures. Notably, this approach is competent to selectively deprotect the allyl or benzyl group, making it a general and practical method in organic synthesis.

Application of two morphologies of Mn2O3for efficient catalyticortho-methylation of 4-chlorophenol

Vapor phaseortho-methylation of 4-chlorophenol with methanol was studied over Mn2O3catalyst with two kinds of morphologies. Here, Mn2O3was prepared by a precipitation and hydrothermal method, and showed the morphology of nanoparticles and nanowires, respectively. XRD characterization and BET results showed that, with the increase of calcination temperature, Mn2O3had a higher crystallinity and a smaller specific surface area. N2adsorption/desorption and TPD measurements indicated that Mn2O3nanowires possessed larger external surface areas and more abundant acid and base sites. Simultaneously, in the fixed bed reactor, methanol was used as the methylation reagent for theortho-methylation reaction of 4-chlorophenol. XRD, XPS, TG-MS and other characterizations made it clear that methanol reduced 4-chlorophenol and its methide, which were the main side-reactions. And Mn3+was reduced to Mn2+under the reaction conditions. Changing the carrier gas N2to a H2/Ar mixture further verified that the hydrogen generated by the decomposition of methanol was not the reason for dechlorination of 4-chlorophenol compounds. Here we summarized the progress of 4-chlorophenol methylation based on the methylation of phenol. Also, we proposed a mechanism of the 4-chlorophenol dechlorination effect which was similar to the Meerwein-Ponndorf-Verley-type (MPV) reaction. The crystal phase and carbon deposition were investigated in different reaction periods by XRD and TG-DTA. The reaction conditions for the two kinds of morphologies of the Mn2O3catalyst such as calcination temperature, reaction temperature, phenol-methanol ratio and reaction space velocity were optimized.