Ethylene glycol dimethacrylate structure

The Effect of Crosslinker Concentration on the Rate of Polymerization. Ethylene glycol dimethacrylate is used most frequently as the crosslinker for HEMA formulations useful in contact lens manufacturing. To demonstrate the effect of crosslinker concentration on the curing rate, formulations derived from HEMA/Glycerine/BME at 85/15/0.17, while varying EGDMA (from 0.34 to 0.68), the peak times were about the same (3.73 and 3.61 minutes respectively). This is reasonable due to the similarity in molecular structure of the crosslinker and the monomer, and the low amount of crosslinker used. The possible presence of other crosslinker, such as the dimerization product of HEMA, is even less a factor to be considered in polymerization kinetics, due to low concentration (normally much less than 0.1 %, in-house information). 

In another report, transparent channels (of width 500-200 pm and depth 50-180 pm) were filled with a photopolymerizable liquid mixture consisting of acrylic acid and 2-hydroxyl methacrylate (1 4 molar ratio), ethylene glycol dimethacrylate (1 wt%), and a photoinitiator (3 wt% Irgacure 651 or 2,2-dimethoxy-2-phenylacetophenone). Polymerization was completed in less than 20 s to produce the hydrogel structures [221]. 

Properties of vinyl compound/phenolic IPN were discussed and the following conclusions drawn. MMA radical polymerization proceeded rapidly in the presence of phenolic resol. Poly (ethylene glycol) dimethacrylate, 23G, and phenolic resol IPNs were synthesized by simultaneous radical polymerization and phenolic resol curing reaction. These IPNs had a structure of poly 23G chains and cured phenolic resol chains so well entangled with each other that the whole acted as a single phase. This type of IPN is considered to... 

Kanerva L, Jolanki R, Leino T, Estlander T. Occupational allergic contact dermatitis from 2-hydroxyethyl methacrylate and ethylene glycol dimethacrylate in a modified acrylic structural adhesive. Contact Dermatitis 1995 33(2) 84-9. 

The structures of some of the molecules generated by pyrolysis of poly(ethylene glycol) dimethacrylate that retain the methacrylic acid (2-methyl-2-propenoic acid) moiety are shown below ... 

A different way to introduce silicone type sequences in copolymers is to attach acrylate end groups to a poly[oxy(dimethylsilylene)], followed by copolymerization in a vinyl type polymer. The introduction of silicone groups leads to a crosslinked material similar to that obtained with poly(ethylene glycol) dimethacrylate. The structure of a copolymer with silicone crosslinking bridges is shown below ... 

Acrylic structural adhesives have been modified by elastomers in order to obtain a phase-separated, toughened system. A significant contribution in this technology has been made in which acrylic adhesives were modified by the addition of chlorosulfonated polyethylene to obtain a phase-separated structural adhesive (11). Such adhesives also contain methyl methacrylate, glacial methacrylic acid, and cross-linkers such as ethylene glycol dimethacrylate [97-90-5]. The polymerization initiation system, which includes cumene hydroperoxide, IV,AT - dimethyl-p- toluidine, and saccharin, can be applied to the adherend surface as a primer, or it can be formulated as the second part of a two-part adhesive. Modification of cyanoacrylates using elastomers has also been attempted copolymers of acrylonitrile, butadiene, and styrene ethylene copolymers with methylacrylate or copolymers of methacrylates with butadiene and styrene have been used. However, because of the extreme reactivity of the monomer, modification of cyanoacrylate adhesives is very difficult and material purity is essential in order to be able to modify the cyanoacrylate without causing premature reaction. 

Several SP materials have been used for the extraction of FRs from aqueous samples, plasma and milk (Table 31.7). Similar materials have been used for all FRs. Typical SP materials include Ci8 and Cg bonded to porous silica, highly cross-linked poly(styrene divinylbenzene) (PS-DVB), and graphitized carbon black (GCB). It is also possible to use XAD-2 resin for extraction of various FRs, pesticides, and plastic additives from large volumes of water (100 1). The analytes can then be either eluted from the resin by acetone hexane mixture, or Soxhlet extracted with acetone and hexane. For a specific determination of diphenyl phosphate in water and urine, molecularly imprinted polymers have been used in the solid phase extraction. The imprinted polymer was prepared using 2-vinylpyridine as the functional monomer, ethylene glycol dimethacrylate as the cross linker, and a structural analog of the analyte as the template molecule. Elution was done with methanol triethylamine as solvent. Also solid phase microextraction (SPME) has been applied in the analysis of PBDEs in water samples. The extraction has been done from a headspace of a heated water sample (100°C) using polydimethylsiloxane (PDMS) or polyacryl (PA) as the fiber material. ... 

It was claimed that the spongelike bicontinuous microemulsion structures could be conserved as microporous (open-pore) polymeric materials with pore size depending on the surfactant concentration, by polymerizing methyl methacrylate and ethylene glycol dimethacrylate in cationic or zwitterionic surfactant systems [123-125]. 

Poly(Propylene Fumarate) (PPF) is a linear, unsaturated, hydrophobic polyester (Structure 12) containing hydrolyzable ester bonds along its backbone. PPF is highly viscous at room temperature and is soluble in chloroform, methylene chloride, tetrahydrofuran, acetone, alcohol, and ethyl acetate [66]. The double bonds of PPF can form chemical crosslinks with various monomers, such as W-vinyl pyrrolidone, poly(ethylene glycol)-dimethacrylate, PPF-diacrylate (PPF-DA), and diethyl fumarate [67,68]. The choice of monomer and radical initiator directly influence the degradative and mechanical properties of the crosslinked polymer. Once crosslinked, PPF forms a solid material with mechanical properties suitable for a range of bone engineering applications. 

Kanerva L, Jolanki R, Leino T, Estlander T (1995b) Occupational allergic contact dermatitis from 2-hydroxyethyl methacrylate and ethylene glycol dimethacrylate in a modified acrylic structure adhesive. Contact Dermatitis 33 84-89 Kanerva L, Keskinen H, Autio P, Estlander T, Tuppurainen M, Jolanki R (1995c) Occupational respiratory and skin sensitization caused by polyfunctional aziridine hardener. Clin Exp Allergy 25 432-439... 

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