Diethylamino ethyl methacrylate

Hydrophobic polymers with some hydrophilic groups can be obtained with an emulsion polymerization technique. Suitable monomers are nitrogen-containing acrylics and methacrylics allyl monomers such as dimethylamino-ethyl methacrylate, dimethylaminopropyl methacrylamide, diethylamino-ethyl methacrylate, dimethylaminoethyl acrylate, diethylaminoethyl acrylate and nitrogen-containing allyl monomers (e.g., diallylamine and N,N-diallyl-cyclohexylamine) [225,226]. 

The polymerization of 2-(diethylamino)ethyl methacrylate, DEAEMA, was studied under different conditions. It was shown that the best system providing narrow molecular weight distribution polymers involved the use of p-toluenesulfonyl chloride/CuCl/HMTETA as the initiator/catalyst/ligand at 60 °C in methanol [72]. Taking advantage of these results, well-defined PDEAEMA-fr-PfBuMA block copolymers were obtained. The synthesis was successful when either fBuMA or DEAEMA was polymerized first. Poor results with bimodal distributions were obtained when CuBr was used as the catalyst. This behavior was attributed to the poor blocking efficiency of PDEAEMA-Br and the incomplete functionalization of the macroinitiator. 

We have recently evaluated the ATRP of a wide range of hydrophilic monomers such as 2-sulfatoethyl methacrylate (SEM), sodium 4-vinylbenzoate (NaVBA), sodium methacrylate (NaMAA), 2-(dimethylamino)ethyl methacrylate (DMA), 2-(iV-morpholino)ethyl methacrylate (MEMA), 2-(diethylamino)ethyl methacrylate (DEA), oligo(ethylene glycol) methacrylate (OEGMA), 2-hydroxyethyl methacrylate (HEMA), glycerol monomethacrylate (GMA), 2-methacryl-oyloxyethyl phosphorylcholine (MPC), and a carboxybetaine-based methacrylate [CBMA]. Their chemical structures and literature references (which contain appropriate experimental details) are summarised in Table 1. 

Chloramphenicol (CL) in serum Diethylamino-ethyl methacrylate (DEAEM) Competitive displacement of CL-methyl red dye conjugate from CL-imprinted polymer packed in HPLC column 3 ug/ml Levi et al., 1997... 

The adsorption of block copolymers can be controlled by different stimuli, in particular by the pH since most of the brushes formed by block copolymers adsorption are polyelectrolyte brushes [129, 130], The group of Armes, for instance, studied the pH-controlled adsorption of a series of block copolymers [131, 132], In the case of copolymers bearing hydrophobic 2-(diethylamino)ethyl methacrylate groups (DEA) and a water-soluble zwiterionic poly(2-methacryloyl phosphoryl-choline) (MPC) block, they showed that at low pH the cationic DEA flatted to the anionic silicon surface while the MPC was in contact with the solution [132], At around neutral pH, micelles were formed in solution and adsorbed onto the surface because the DEA core was still weakly cationic. The MPC block formed the micelle coronas. Nevertheless, at higher pH the micelles became less cationic and the adsorption rate decreased. 

The different situations of the block copolyampholyte as a function of pH are depicted in Scheme. 1. The same order of deprotonation was observed in copolymers of poly(methacrylic acid) and poly(2-(diethylamino)ethyl methacrylate) [70, 71, 72, 75-77]. In copolymers of poly(methacrylic acid) [78] and poly(2/4-vinylpyridine), on the other hand, deprotonation of the pyridine hydrochloride takes place prior to deprotonation of the carboxyl [79-83] because in comparison to carboxylic functionalities amine hydrochlorides are the weaker acids and vinylpyridinium hydrochlorides the stronger ones. Thus, in the latter systems an isoelectric point (iep) is not observable, while in the first case polyzwitterions are formed which possess the highest amount of charges at that pH resulting in a polyelectrolyte complex (PEC). In the second case polymers with a minimal net charge built the PEC which is stabilized by hydrophobic interactions often accompanied by hydrogen bonding [79, 84-88]. 

Capek described the use of a macromonomer in miniemulsion polymerization [54]. Lim and Chen used polyfmethyl methacrylate-fr-(diethylamino)ethyl methacrylate) diblock copolymer as surfactant and hexadecane as hydrophobe for the stabilization of miniemulsions [55]. Particles with sizes between about 150 and 400 nm were produced. It is possible to create stable vinyl acetate miniemulsions employing nonionic polyvinyl alcohol (PVA) as surfactant and hexadecane as hydrophobe [56]. 

Armes et al. [49] have reported the use of pH-responsive microgels based solely on 2-(diethylamino)ethyl methacrylate (DEA) as colloidal templates for the in situ synthesis of Pt nanoparticles (PtNPs). The swollen microgels can be used as nanoreactors efficient impregnation with PtNPs can be achieved by incorporating precursor platinum compounds, followed by metal reduction. Addition of platinic acid, H2PtCl6, to the latex particles causes the protonation of the tertiary amine... 

Figure 6.37. Synthetic scheme for three-layer cross-linked micelles. Shown is the micellation of poly[(ethylene oxide)-block-glycerol monomethacrylate-block-2-(diethylamino)ethyl methacrylate] (PEO-GMA-DEA) triblock copolymers to the final onion-like" layered nanostructure. Reproduced with permission from Liu, S. Weaver, J. V. M. Save, M. Armes, S. P. Langmuir 2002, 18, 8350. Copyright 2002 American Chemical Society.

Block copolymers of 23b and alkyl methacrylates [158] and diblock copolymers of 23b with 2-(diethylamino)ethyl methacrylate (23b-DEAEM), 2-(diisopropylamino)ethyl methacrylate (23b-DIPAEM), or 2-(N-morphoHno) ethyl methacrylate (23b-MEMA) exhibited reversible pH-, salt-, and temperature-induced micellization in aqueous solution under various conditions. The micelle diameters were 10-46 nm [238]. The micelles of these hydropho-bically modified polybetaines consist of coronas from 23b and cores from polyDEAEM, polyDIPAEM, or polyMEMA. In aqueous solution, the 23b-MEMA diblock copolymers form micelles with cores of polyMEMA above an upper critical micelle temperature of about 50 °C, and reversibly betainized-DMAEM core micelles below a lower critical micelle temperature of approximately 20 °C [239]. 

N-(2-hydroxypropyl) methacrylamide Poly(ethyleneoxide)dimethacrylate 2-(dimethylamino)ethyl methacrylate 2-(diethylamino)ethyl methacrylate (HPMA) (PEODM) (DMAEMA) (DEAEMA)... 

Quartz crystal microbalance (QCM) Surface plasmon resonance (SPR) Piezoelectric quartz crystal (PQC) Bulk acoustic wave (BAW) surface acoustic wave (SAW) 4-vinylpyridine (4-VP) Ethylene glycol dimethacrylate (EDMA) Methacrylic acid (MAA), Ethylene glycol dimethacrylate (EDMA) IV-phenylacrylamide (PAM) Diethylamino ethyl methacrylate (DEAEM). 

Those nanoparticles (3LNPs) were fabricated via a pH-controlled hierarchical self-assembly of a tercopolymer brush (Schemes 10.2 and 10.3), which contained hydrophilic polycaprolactone (PCL) chains, water-soluble PEG chains, and pH-responsive poly[2-(iV,iV-diethylamino)ethyl methacrylate] (PDEA) chains. PDEA is a polybase that is soluble at low pH but insoluble at neutral pH [167-169]. The brush polymer was initially dispersed in a pH 5.0 solution where the PDEA chains were protonated and hence water-soluble. The hydrophobic PCL chains and drug molecules associated to form the hydrophobic core. The PEG and protonated PDEA chains formed a hydrophilic corona surrounding the core. After the solution pH was raised to 7.4, the PDEA chains were deprotonated and became hydrophobic, collapsing on the PCL core as a hydrophobic middle layer with only the PEG chains forming the hydrophilic corona (Scheme 10.3). 

Fig. 10.17 Cytoplasmic drug delivery using lysosomal-pH-responsive fast-release nanoparticles a the nanoparticle is internalized by endocytosis b transferred to a lysosome c the PDEA core is protonated at the lysosomal pH (4-5) and the nanoparticle dissolves, releasing the drug into the lysosome d the continuous PDEA (poly[2-(JV,A-diethylamino)ethyl methacrylate]) protonation causes an osmotic imbalance across the lysosome membrane, which finally ruptures the lysosome and hence releases the drug into cytoplasm...

Researchers have also used pyrene dispersed as a probe to provide information regarding the nature of the micellar core formed from block copolymers of 2-(dimethylamino)ethyl methacrylate (DMAEMA) and methacrylic acid [167] and DMAEMA with 2-(diethylamino)ethyl methacrylate (DEAEMA) [166], A similar degree of hydrophobicity in the micellar cores, as sensed by the probe, was determined in both types of block copolymers. 

By polymerizing poly(A -isopropylacrylamide) (PNIPAM) [55] or poly (2-(diethylamino)ethyl methacrylate) (PDEAEMA) [56] as a stimuli responsive polymer/hydrogel layer around a colored nanoparticle of PS-co-PMMA, the local refractive index and consequently the color intensity of the latex could be switched by the temperature [55] or pH [56]. 

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