“Smart” poly(2‐(dimethylamino)ethyl methacrylate‐<i>ran</i>‐9‐(4‐vinylbenzyl)‐9H‐carbazole) copolymers synthesized by nitroxide mediated radical polymerization

2013

Express Polym. Lett.

Abstract. The homopolymerization of phenyl acrylate (PA) was investigated for the first time by nitroxide mediated polymerization (NMP) with the succinimidyl form of the SG1-based unimolecular initiator 2-[N-tert-butyl-2,2-(dimethylpropyl)-aminooxy]propionic acid (BlocBuilder MA). The control of PPA homopolymerization was improved by the use of 15 mol% additional free nitroxide SG1 ([tert-butyl[1-(diethoxyphosphoryl)-2,2-dimethylpropyl]amino]oxidanyl) and dispersities, M w /M n , of around 1.2 were achieved. A PPA homopolymer was then successfully chain-extended with diethyl acrylamide (DEAAm) to form a block copolymer of PPA-b-PDEAAm where the PDEAAm segment is thermo-responsive, while the PPA block is potentially UV-active. The thermo-responsive behavior of the block copolymer in 0.5 wt% aqueous solution was studied by UV-Vis spectrometry and dynamic light scattering (DLS), indicating cloud point temperatures of 26-30°C, close to that reported for PDEAAm homopolymers.

Section: Thermo-responsive Behavior Illustratedmentioning

confidence: 71%

Section: Thermo-responsive Behavior Illustratedmentioning

confidence: 99%

Thermo-responsive, UV-active poly(phenyl acrylate)-b-poly(diethyl acrylamide) block copolymers

Wang¹,

Lessard²,

2013

Express Polym. Lett.

“…The copolymers were dissolved in either aqueous solution at different concentrations or in buffer solutions from pH 4 to 11 at 0.5 wt % concentration and their temperature response was monitored by UV-Vis spectroscopy (see Tables S2 and S3 in The LCST can be affected by many parameters, such as copolymer composition, 49,64 solution concentration, 64 pH, 64,65 and heating rate. 43,44,66,67 The effect of copolymer composition on CPT was studied since incorporation of VPBA into the copolymer would alter the phase separation temperature.…”

Section: Complexation Of Boron With the Tertiary Aminementioning

confidence: 99%

Vinyl phenylboronic acid controlling co‐monomer for nitroxide mediated synthesis of thermoresponsive poly(2‐N morpholinoethyl methacrylate)

Savelyeva

Chondon

J. Polym. Sci. Part A: Polym. Chem.

2015

Self Cite

Low concentrations of 4-vinylphenylboronic acid (VPBA) were copolymerized with 2-N-morpholinoethyl methacrylate (MEMA) by nitroxide mediated polymerization using BlocBuilder TM unimolecular initiator at 80 to 90 8C. The MEMA/VPBA copolymerizations were performed at initial feed compositions (f VPBA,0 ) of 0.05 to 0.10 VPBA, with f VPBA,0 5 0.10 using dimethylacetamide (DMAc) solvent being most effective, as seen by a linear increase in number average molecular weight, M n , versus conversion and low dispersity, -D < 1.40. The copolymers were further chain-extended with a second batch of VPBA, resulting in a block copolymer with monomodal molecular weight distribution and -D 5 1.66. For MEMA/VPBA copolymers, increases in VPBA composition and polymer solution concentration resulted in decreases in the cloud point temperature (CPT, typically varied between 27.4-37.8 8C) and CPT increased from 31.2 to 33.8 8C to about 88 8C with decreases in pH from 7 to 4. Rheological tests with small angle light scattering (SALS) confirmed CPTs measured by UV-Vis and DLS. These copolymers were targeted as models to combine possible glucose-sensing boronic acid functionality the thermoresponsiveness provided by MEMA groups. V C 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016Chem. , 54, 1560Chem. -1572

“…The copolymerization approach reported by Charleux and co‐workers (adding ≈5 mol% of a monomer that is well‐controlled by NMP such as a styrenic) was quite useful with N‐( 2‐methylpropyl)‐ N ‐(1‐(diethylphosphono‐2,2‐dimethylpropyl)‐ O ‐(2‐carboxylprop‐2‐yl)hydroxylamine) (BlocBuilder) type unimolecular initiators and has been widely adopted. For example, it has been used in the polymerization of methyl methacrylate (MMA), methacrylic acid (MAA), benzyl methacrylate, (dimethylamino) ethyl methacrylate, and poly(ethylene glycol) methyl ether methacrylate . The most widely used comonomers via this approach are styrene or styrenic derivatives, 9‐(4‐vinylbenzyl)‐9H‐carbazole (VBK), and acrylonitrile …”

Section: Introductionmentioning

confidence: 99%

“…The choice of the controlling comonomer can have a secondary purpose; it can impart functionality. For example, it can be used to add water‐solubility (e.g., styrene sulfonic acid, sodium salt) or fluorescent properties (VBK) . In some cases, the media used for the polymerization may prevent usage of a monomer.…”

Section: Introductionmentioning

confidence: 99%

Nitroxide‐Mediated Polymerization of 2‐Hydroxyethyl Methacrylate (HEMA) Controlled with Low Concentrations of Acrylonitrile and Styrene

Mei

Macro Reaction Engineering

2017

Nitroxide‐mediated controlled radical polymerization of 2‐hydroxyethyl methacrylate (HEMA) is achieved using the copolymerization method with a small initial concentration of acrylonitrile (AN, 5–16 mol%)) or styrene (S, 5–10 mol%). The polymerization is mediated by N‐tert‐butyl‐N‐(1‐diethyl phosphono‐2,2‐dimethyl propyl) nitroxide (SG1)‐based BlocBuilder unimolecular alkoxyamine initiator modified with an N‐succinimidyl ester group (N‐hydroxysuccinimide‐BlocBuilder). As little as 5% molar feed of acrylonitrile results in a controlled polymerization, as evidenced by a linear increase in number average molecular weight Mn with conversion and dispersities (Đ) as low as 1.30 at 80% conversion in N,N‐dimethylformamide (DMF) at 85 °C. With S as the controlling comonomer, higher initial S composition (≈10 mol%) is required to maintain the controlled copolymerization. Poly(HEMA‐ran‐AN)s with Mn ranging from 5 to 20 kg mol−1 are efficiently chain extended using n‐butyl methacrylate/styrene mixtures at 90.0 °C in DMF, thereby showing a route to HEMA‐based amphiphilic block copolymers via nitroxide‐mediated polymerization.