EGMEMA vs. EGMEA - important distinction: Despite similar names, these are entirely different products. EGMEA (CAS 110-49-6) is a passive solvent (acetate ester, Repr. 1B classified). EGMEMA (CAS 69769-38-8) is a reactive polymerizable monomer (methacrylate ester, not Repr. 1B, no SVHC). Always verify CAS numbers when ordering - the two compounds have no interchangeable application.

Structure & Polymerization Notes EGMEMA condensed structure: CH₂=C(CH₃)–COO–CH₂CH₂–OCH₃. The methacryloyl group (vinyl + α-methyl) reacts readily with standard radical initiators - ammonium persulfate (APS), redox systems, azo compounds - under solution or emulsion polymerization conditions at 60–90°C. It is also compatible with RAFT and ATRP controlled radical polymerization for precision block copolymer and narrow-dispersity polymer synthesis.  |   Side chain contribution: Each EGMEMA molecule contributes exactly 2 ethylene oxide (EO) units to the polymer side chain, capped with a methyl group - the defining structural feature for PCE "short-chain" architecture.  |   MEHQ inhibitor oxygen dependency: MEHQ inhibitor requires dissolved oxygen to function. Do NOT store EGMEMA under full nitrogen blanket without confirming inhibitor level sufficiency - oxygen-free storage can deplete inhibitor efficacy and trigger runaway polymerization.

Specification Item	Standard / Value	Test Method / Process Significance
Appearance	Colorless transparent liquid	Visual; no color = no oxidative degradation / radical scavengers
Purity (GC)	≥ 99.0%	GC area normalization; ensures reproducible copolymerization kinetics
Inhibitor (MEHQ)	100–200 ppm	UV spectrophotometry; consistent level = predictable induction period
Acid Value (as MAA)	≤ 0.1%	Potentiometric titration; excess MAA causes uncontrolled chain transfer
Water Content	≤ 0.1%	Karl Fischer; prevents ester hydrolysis, ensures consistent reactivity
Color (Pt-Co)	≤ 10	Colorimeter; color indicates oxidative degradation products = radical scavengers
Density (d20)	~1.003 g/cm³	Digital density meter; identity confirmation
Boiling Point	~190–192 °C	Low vapor pressure; reduced ambient vapor exposure vs MMA or EA
Flash Point	~82 °C (closed cup)	Combustible liquid - standard flammable handling; much safer than MMA
Refractive Index	~1.432 (n20/D)	Refractometer; purity and identity check
Packaging	200 kg sealed drum  /  IBC on request	N₂-padded drums available for O₂-sensitive applications

The largest commercial application of EGMEMA globally is as a short-chain ether comonomer in PCE (polycarboxylate ether) superplasticizer synthesis. PCE superplasticizers are amphiphilic comb-type copolymers that dominate modern high-performance concrete construction - their steric repulsion mechanism delivers superior water reduction (≥12–35% depending on dosage and formulation) vs earlier-generation sulfonated naphthalene or melamine formaldehyde water reducers.

When copolymerized with acrylic acid (AA), methacrylic acid (MAA), or maleic anhydride (MA) using persulfate/redox initiation in aqueous solution polymerization at 70–85°C, EGMEMA contributes exactly 2 ethylene oxide (EO) units per side chain to the PCE comb architecture. These dense, short ether side chains maximize cement surface adsorption capacity - particularly important in cement formulations with high C₃A content, which can rapidly consume adsorbed PCE molecules through aluminate phase intercalation.

PCE Comb-Polymer Architecture - Role of Each Component

In waterborne coating emulsion polymerization, EGMEMA is incorporated alongside core monomers (MMA, BA, EA, St) as a functional hydrophilic comonomer. Its ether segments improve latex particle surface compatibility with water-phase pigments, dispersants, and thickeners; extend open time in architectural paints by retaining surface moisture during application; and enhance adhesion to polar and damp substrates via hydrogen bonding between ether oxygens and substrate hydroxyl groups.

For industrial waterborne coatings on metal substrates - where adhesion to bare metal, phosphated, or chromated surfaces determines corrosion protection service life - EGMEMA's contribution to substrate wetting and adhesion can be the difference between coating system pass and fail. Its dual compatibility with both polar (resin backbone, pigment surfaces) and non-polar (hydrophobic comonomer, plasticizer) domains makes it an effective internal compatibilizer in complex multi-component emulsion formulations.

EGMEMA-based acrylic polymers applied to cotton, polyester, nylon, and blended fabrics via padding, exhaust, or spray impart: improved moisture wicking (ether segment hydrophilicity), reduced static charge accumulation (polar ether side chains), and soft hand feel without the tackiness of purely hydrophobic polymer finishes. In functional textiles - sportswear, medical textiles requiring hydrophilic surfaces, and workwear for cleanroom or explosive-atmosphere environments requiring antistatic performance - EGMEMA-based finishing polymers provide durable functional performance that persists through multiple wash cycles due to strong physical bonding between the polymer film and fiber substrate.

Water treatment: Copolymerized with acrylic acid and AMPS, EGMEMA produces amphiphilic scale inhibitors and dispersants for cooling water systems, boiler water treatment (ether groups more thermally stable than hydroxyl groups above 120°C), RO membrane antifouling, and mining process water management. The ether functionality improves thermal stability and dispersancy for calcium carbonate and calcium sulfate scale minerals.

UV-curable systems: EGMEMA is fully compatible with UV-radical polymerization using standard Type I and Type II photoinitiators (315–400 nm). Used as a reactive diluent in UV-curable coatings, adhesives, and inks - reducing viscosity while contributing hydrophilic ether functionality to the cured film for improved substrate adhesion on polar surfaces. Its high boiling point (190°C) reduces workplace vapor exposure and film volume loss during UV processing vs lower-boiling acrylate diluents.

Controlled radical polymerization (RAFT / ATRP): EGMEMA is compatible with RAFT and ATRP for precision synthesis of amphiphilic block copolymers, responsive hydrogels, pressure-sensitive adhesives, and biomedical polymer systems. For RAFT/ATRP, inhibitor removal by vacuum distillation or inhibitor-removal column is typically required before polymerization to achieve predictable induction periods and controlled chain growth at low initiator concentrations.

Property	EGMEMA CAS 69769-38-8	HEMA CAS 868-77-9	PEGMA (various MW) Long-chain PEG
Side Chain	–CH₂CH₂OCH₃ (short ether, 2 EO)	–CH₂CH₂OH (hydroxyl)	–(CH₂CH₂O)ₙH (long PEG, 8–23 EO)
Mol. Weight (g/mol)	144.17	130.14	360–1000+ (varies with MW)
Hydrophilicity	Moderate (ether)	High (hydroxyl)	Very High (PEG)
PCE Side-Chain EO Units	2 EO (short-chain PCE)	Not used in PCE	8–23 EO (long-chain PCE)
PCE Water Reduction	High (dense short-chain comb)	N/A	Moderate–High (spaced comb)
PCE Slump Retention	Good (dense adsorption)	N/A	Excellent (steric PEG bulk)
Cost (relative)	Low–Moderate ✓	Low ✓	High (MW-dependent)
Concrete Target Application	Precast, UHPC, high early-strength	N/A	SCC, ready-mix, complex formwork
EU Repr. Classification	Not classified ✓	Not classified ✓	Not classified ✓

⚠️ SELF-POLYMERIZATION RISK: EGMEMA is a reactive monomer stabilized with 100–200 ppm MEHQ. Exposure to heat (>30°C), UV/visible light, radical initiators, or strong oxidizers can trigger runaway self-polymerization - generating significant heat. Inspect drums for increased viscosity, discoloration, or gelation before opening. Do NOT heat drums showing any sign of self-polymerization.

🚫 OXYGEN REQUIREMENT: MEHQ inhibitor requires dissolved oxygen to function. Do NOT store EGMEMA under full nitrogen blanket without first confirming sufficient inhibitor level - oxygen-free conditions can deplete inhibitor efficacy. Maintain normal air atmosphere in partially emptied drums.

Q: What is the difference between EGMEMA (CAS 69769-38-8) and EGMEA (CAS 110-49-6)?

Despite nearly identical abbreviations, these are entirely different compounds. EGMEA (CAS 110-49-6) is the acetate ester of EGME - a passive solvent used to dissolve resins, coatings, and inks. It carries EU Repr. 1B classification. EGMEMA (CAS 69769-38-8) is the methacrylate ester of EGME - a reactive polymerizable monomer that covalently incorporates into polymer chains during free-radical polymerization. It is not classified as Repr. 1B, has no SVHC status, and has completely different applications (PCE synthesis, emulsion polymerization). Always verify CAS numbers - these compounds cannot be substituted for each other in any application.

Q: How does EGMEMA content affect PCE superplasticizer water reduction and slump retention?

In PCE comb-polymer architecture, each EGMEMA molecule contributes exactly 2 ethylene oxide (EO) units per side chain. Higher EGMEMA mole fraction in the PCE feed increases the density of short ether side chains on the backbone - maximizing cement surface adsorption capacity (more carboxylate anchor groups per backbone unit length) and accelerating cement particle dispersion, yielding higher initial water reduction at standard dosage (0.1–0.3% bwc). The trade-off: shorter side chains provide less steric bulk to resist hydration-driven reconsolidation over 30–90 minute timeframes - slump retention is shorter. PCE formulators targeting very high water reduction (>30%) for precast or UHPC use EGMEMA as the primary side-chain monomer; those targeting 60–90 min slump retention for ready-mix blend EGMEMA with longer-chain PEGMA co-monomers.

Q: What MEHQ inhibitor level is in Sinolook's EGMEMA, and do I need to remove it before PCE synthesis?

Sinolook's standard EGMEMA contains 100–200 ppm MEHQ, verified by UV spectrophotometry on every batch. For PCE synthesis in aqueous solution polymerization at 70–85°C using persulfate or redox initiation, this inhibitor level is typically consumed during the polymerization induction period and does not require removal - simply design your process to account for a short induction period before chain growth commences. For RAFT or ATRP controlled radical polymerization, where low initiator concentrations are used, inhibitor removal by vacuum distillation or inhibitor-removal column is recommended to achieve predictable induction period length and controlled chain growth. Contact our technical team for guidance specific to your polymerization system.

Q: What target molecular weight should EGMEMA-based PCE aim for?

Optimal PCE molecular weight for concrete admixture performance is typically Mw 20,000–80,000 g/mol with dispersity Ð < 2.0. For EGMEMA-rich PCE targeting precast and high early-strength applications, Mw in the 25,000–45,000 g/mol range with a carboxylate backbone:ether side-chain molar ratio of approximately 3:1 to 5:1 is widely reported as optimal. Chain transfer agent (mercaptopropionic acid or sodium methallyl sulfonate) dosage is the primary variable for MW control. Sinolook provides technical guidance on CTA selection and dosage for customers developing new EGMEMA-based PCE formulations.

Q: Can EGMEMA be used in UV-curable coating and adhesive systems?

Yes - EGMEMA is fully compatible with UV-radical polymerization using standard Type I photoinitiators (benzoin ethers, acyl phosphine oxides) and Type II systems (benzophenone/amine synergist) at 315–400 nm wavelength (UV-A/UV-B lamp or LED). It functions as a reactive diluent monomer in UV-curable coatings, adhesives, and inks - reducing formulation viscosity while contributing hydrophilic ether functionality to the cured film for improved adhesion on polar substrates and better compatibility with hydrophilic pigments. Its high boiling point (~190°C) reduces workplace vapor exposure and coating film volume loss during UV processing compared to monofunctional acrylate reactive diluents with lower boiling points.

Related products: HEMA (2-Hydroxyethyl Methacrylate)  ·  PEGMA (PEG Methacrylate, various MW)  ·  Methacrylic Acid (MAA)  ·  Acrylic Acid (AA)  ·  EGME (Ethylene Glycol Monomethyl Ether)  ·  EGMEA (Ethylene Glycol Monomethyl Ether Acetate)  ·  MMA (Methyl Methacrylate)