OEGMA {Oligo(ethylene glycol) methyl ether methacrylate} as Crosslinking Monomer for Gel Polymer Electrolytes (GPEs), CGPEMOEGMA

OEGMA (Oligo(ethylene glycol) Methyl Ether Methacrylate) is one of the most effective monomers for fabricating next-generation gel polymer electrolytes (GPEs). It serves as a structural bridge between traditional poly(ethylene oxide) (PEO) solid-state electrolytes and liquid electrolytes. Chemically, an OEGMA monomer consists of a polymerizable methacrylate backbone attached to a short, flexible oligo(ethylene glycol) (OEG) side chain—essentially a short pendant piece of PEO terminating in a methyl ether group.

 When OEGMA is polymerized in situ, it forms a "comb-like" or "bottle-brush" polymer architecture. This structural layout provides distinct thermodynamic and kinetic advantages for ion transport: (1) Suppressed Crystallinity: Traditional high-molecular-weight PEO is highly crystalline at room temperature, which locks the polymer chains in place and drops ionic conductivity to impractical levels (10^{-7} to 10^{-6} S cm-1). The dangling side chains of poly-OEGMA are too short to organize into a crystalline lattice. This keeps the matrix highly amorphous, lowering the glass transition temperature (Tg) and keeping the chains flexible. (2) Decoupled Ion Transport: In classic PEO, lithium or sodium ions migrate via the slow, cooperative segment motion of the main polymer backbone. In poly-OEGMA, the highly flexible, fast-moving side chains act as rapid "ion-conduction highways." The cations coordinate with the ether oxygens (C-O-C) on these side chains, allowing rapid hopping that is partially decoupled from the main chain movement.

To form a dimensionally stable gel that won't leak under pouch-cell calendering or cycling pressure, OEGMA is co-polymerized in situ with a multi-functional crosslinker like PEGDA (Polyethylene Glycol Diacrylate) or ETPTA. Typical Precursor Formulation: 80–90 wt% OEGMA (for high ionic mobility) + 10–20 wt% PEGDA (for 3D structural network) + Liquid Electrolyte (Salt + Solvent) + Thermal Initiator (AIBN).

The electron-donating ether groups in OEGMA make it susceptible to oxidative decomposition at high potentials (typically limited to around 4.2V vs. Li/Li+). To push OEGMA gels into high-voltage territory (such as ultra-high nickel NCM or high-voltage sodium layered oxides), it is often co-polymerized with fluorinated or cyano-functionalized monomers like TFEMA (2,2,2-Trifluoroethyl Methacrylate) or AN (Acrylonitrile). The electron-withdrawing co-monomers lower the HOMO level of the final gel matrix, stabilizing it against high-voltage cathode surfaces.

Part Number	CGPEMOEGMA (C-GPE-M-OEGMA)
CAS	26915-72-0
Chemical Formula	H2C=C(CH3)COO(CH2CH2O)nCH3
Average Molecular Weight	Mw= 300-950, liquid Mw=2000, solid powder
Density	~1.05 g/mL at 25 °C
Package Size	100 g/bottle (liquid), 5 g/bottle (solid powder)

Notes: Please try to store the OEGMA monomer in a dry place. 

References: 

1. S. D. Tillmann, et al. Gel polymer electrolyte for lithium-ion batteries comprising cyclic carbonate moieties, Journal of Power Sources, 2014, 271, 239-244
2. P. Isken, et al. Methacrylate based gel polymer electrolyte for lithium-ion batteries, Journal of Power Sources, 2013, 225, 157-162