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Sequential group transfer polymerization of cross-linker, monomer (methyl methacrylate), and cross-linker again is used to prepare cleavable polymer networks based on interconnected “core-first” star polymers. By employing a degradable and a nondegradable cross-linker, four networks are prepared. While cleavage of the degradable cross-linker residues leads to complete polymer network dissolution, the degradation products do not always display the expected molecular weight features. These products are the expected in the case of the network prepared using only the degradable cross-linker (monomodal size distribution with expected low molecular weight) and also in the case of the network prepared using first the degradable and then the nondegradable cross-linker (bimodal size distribution including high molecular weight star polymers), but not so in the case of the network prepared using first the nondegradable and then the degradable cross-linker, where the expected high molecular weight star polymer component is missing due to star recombination after hydrolysis. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim 219 1

In this study, a series of microencapsulated phase change materials with poly(methyl methacrylate-co-methacrylic acid) P(MMA-co-MAA) shell and n-octadecane or n-eicosane core were synthesized by emulsion polymerization method. The aim was to produce microencapsulated n-alkanes having functional groups on their outer surface, so that functional groups would help increasing physical interactions between microcapsules and fiber surface. Therefore, methyl methacrylate (MMA), ethylene glycoldimethacrylate (EGDM), and methacrylic acid (MAA) were copolymerized in oil phase of n-alkane. FT-IR results proved the successful synthesis of P(MMA-co-MAA) shell of microencapsulated n-alkanes. The DSC results indicated that the microencapsulated n-alkanes have considerable latent heat storage capacity in a range of 58-145J/g. The average melting and freezing temperatures of the microencapsulated n-alkanes were measured as 27 and 26 degrees C for n-octadecane and 36 and 35 degrees C for n-eicosane, respectively. The microcapsules were of spherical and compact shape with particle sizes between 15 and 32m. The microcapsules on the cotton fabric applied by pad-dry-cure method were found highly durable and they showed sufficient stability upon several washings and rub fastness. Thermo-regulating properties of the fabrics were declared as a result of thermal history measurements.

High-molecular-weight (MW) symmetrical multiblock copolymers, based on the hydrophobic monomers styrene (Sty) and methyl methacrylate (MMA), and the more polar monomer, 2-vinyl pyridine (2VPy), were prepared using stepwise reversible addition-fragmentation chain transfer polymerization. All copolymers shared a common poly(ethylene glycol) (PEG) midblock, introduced as a bifunctional macromolecular chain transfer agent. In total, five ABA triblock copolymers, five ABCBA pentablock terpolymers, and two ABCDCBA heptablock quaterpolymers (comprising four different monomer types) were synthesized. The MWs of the multiblock polymers were determined using gel permeation chromatography (GPC) and proton nuclear magnetic resonance (1H NMR) spectroscopy, with the latter values being closer to the theoretically expected, whereas GPC MW distributions were relatively narrow, broadening with the number of blocks. The compositions of the synthesized polymers, as determined by 1H NMR spectroscopy, were also close to the expected values. Finally, films cast from chloroform solutions of the pentablock terpolymers P2VPy-b-PSty-b-PEG-b-PSty-b-P2VPy, PSty-b-PMMA-b-PEG-b-PMMA-b-PSty, and P2VPy-b-PMMA-b-PEG-b-PMMA-b-P2VPy examined using transmission electron microscopy exhibited PSty and PMMA cylinders (first two) and lamellae (third terpolymer). © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 4957–4965

Two series of polyampholyte (PA) hydrogels were prepared via reversible addition-fragmentation chain transfer polymerization, followed by removal of the protecting group of the acidic monomer repeating units (methacrylic acid, MAA), which were common in both series. One series bore (pyridin-2-yl)methyl methacrylate (2PyMMA) basic monomer repeating units, whereas the second series carried basic monomer repeating units of 2-(dimethylamino)ethyl methacrylate (DMAEMA). The 2PyMMA-MAA combination in the first series had the peculiarity that the basic 2PyMMA units were more acidic than the MAA units, thus resulting in so-called inverse PA hydrogels. The DMAEMA-MAA pair in the other series led to regular PA hydrogels in which the basicity and acidity of the two types of units were in the conventional sense. The swelling and hydrogen ion equilibrium properties of the two series were explored and thoroughly compared to each other. The aqueous degrees of swelling of inverse PA hydrogels were found to be generally lower than those of the regular ones due to the more hydrophobic character of the 2PyMMA basic units employed in inverse compared to those (DMAEMA) in regular PA gels. The aqueous swelling pH-profiles in both series of PA hydrogels presented a minimum. However, this swelling minimum was deeper and wider in the case of inverse PA hydrogels, because of the greater hydrophobicity of the basic (2PyMMA) units and the greater difference in the effective pK values of the two types of units (2PyMMA-MAA) in inverse PA hydrogels, respectively. This larger separation of the pK in inverse PA gels was directly confirmed from the hydrogen ion titration curves of all the gels. Finally, the isoelectric points of inverse PA hydrogels possessed no detectable dependence on PA composition, which must be contrasted to the strong composition-dependence of the isoelectric points of regular PAs. © 2016 American Chemical Society. 49 10 3869 3880 Cited By :6

A novel bifunctional bis(hemiacetal ester) chain transfer agent (CTA), 1,2-bis[1-(4-cyano-4-methyl-1-oxo-4-(phenylcarbonothioylthio)butanoxy)ethoxy] ethane (CMPTBEE), appropriate for the reversible addition-fragmentation chain transfer (RAFT) polymerization of methacrylate monomers, was successfully synthesized and used for the preparation of a family of 10 hydrolyzable end-linked polymer (co)networks. The family comprised three methyl methacrylate (MMA) homopolymer networks with different degrees of polymerization, 100, 150, and 200, and seven end-linked amphiphilic polymer conetworks of MMA and 2-(dimethylamino)ethyl methacrylate (DMAEMA) with a constant overall degree of polymerization equal to 200 but various compositions and architectures. The agreement of the experimentally measured molecular weights with the theoretically expected ones and the low molecular weight dispersities of the linear precursors to the (co)networks indicated successful control of the polymerization. All (co)networks were characterized in terms of their sol fraction and in terms of their degree of swelling in THF. The value of the former was found in the range between 4 and 50%, whereas that of the latter was around 13%. The presence of the hemiacetal ester groups allowed the hydrolysis of the most hydrophilic, DMAEMA-rich conetworks. The resistance to hydrolysis of the other (co)networks could be attributed to the large hydrophobic blocks surrounding and protecting from hydrolysis the hemiacetal ester groups of the CTA residue in the conetworks. © 2012 American Chemical Society. 45 19 7890 7899 Cited By :22

Dispersion of fullerene, C 60, by addition of polymethacrylate dispersant in methyl methacrylate (MMA) and incorporation of C 60 into poly(methyl methacrylate) (PMMA) were investigated. Copolymers synthesized by radical copolymerization of MMA and 2-naphthyl methacrylate (NMA), poly(MMA-co-NMA), effectively dispersed C 60 in MMA to form clusters of 20 nm. In these cases, addition of minimal 110 naphthyl groups per unit C 60 molecule afforded to give clusters with minimum of 20 nm sizes. Furthermore, block copolymers, poly(MMA-b-NMA) with MMA/NMA mole ratio from 12:1 to 20:1, also efficiently dispersed C 60 to give formation of clusters of 20 nm size by addition of minimal 40 naphthyl groups per unit C 60 molecule, which was corresponding to approximate nine layers of naphthyl group in block copolymer adsorbed on the surface of the cluster. Hybrid films of C 60/PMMA, prepared by casting of C 60-dispersed solution containing PMMA, exhibited absorbance at 400 nm linearly increased with C 60 content., Colloid and Polymer Science, 290(12), pp.1221-1226; 2012

Polystyrene, poly(methylacrylate) and poly(methyl methacrylate) four and three-arm stars were synthesized by Reversible Addition Fragmentation chain-Transfer (RAFT) polymerization by using two new dithioester-derived chain transfer agents [CTA or R-S-(C = S)Z]), CTA-1 and CTA-2. CTA-1 is a four arm CTA while CTA-2 is a three-arm CTA. These were easily synthesized from commercially available reagents and were characterized by spectroscopic techniques such as 1H-NMR, 13C-NMR, IR and mass spectrometry. It is demonstrated that the two new CTAs enable the growth of arms away from the core (i.e., core first approach). An attempt has been made to study the effect of the structure of the R-group, which is present as the core in the CTA, on the polymerization, by analyzing the detailed kinetics. This study suggests that CTA-2, with a benzylic R group, enables the controlled star polymerization of styrene while CTA-1, with a R group similar in structure to the propagating radical derived from the polymerization of methyl acrylate (MA), enables the controlled polymerization of MA although to a lesser extent. This study also reveals that the temperature of free radical initiated RAFT (star) polymerization should be chosen in such a way that it is a compromise between reasonable rate of homolysis of the initiator and the CTA (R-group). � Taylor & Francis Group, LLC.

Tiglic acid esters are naturally derived olefins of pleasant odor but incapable of undergoing free-radical polymerization due to the steric hindrances conferred by the β-methyl group. In an effort to incorporate these green olefins in well-defined (co)polymers, we first established that methyl tiglate, the simplest tiglic acid ester, could not be polymerized using controlled polymerization techniques either, and we then introduced it in a methacrylate monomer, 2-(methacryloyloxy)ethyl tiglate (MAET), which could smoothly undergo group transfer polymerization (GTP) to yield linear polymers of narrow molecular weight distributions. Subsequently, amphiphilic and double-hydrophobic block copolymers, as well as a star polymer of MAET were obtained by its sequential GTP with 2-(dimethylamino)ethyl methacrylate, methyl methacrylate, and ethylene glycol dimethacrylate, respectively. Finally, polyMAET was selectively oxidized. © 2010 American Chemical Society. 43 3 1411 1415 Cited By :10

Semisegmented amphiphilic polymer conetworks (APCNs) based on the hydrophilic monomer 2-(dimethylamino)ethyl methacrylate (DMAEMA), the hydrophobic monomer methyl methacrylate (MMA), and the hydrophobic cross-linker ethylene glycol dimethacrylate (EGDMA) were prepared using group transfer polymerization in a two-step procedure that involved the synthesis of linear polyDMAEMA or polyMMA arms, followed by their cross-linking using a mixture of EGDMA with either MMA or DMAEMA, respectively. Four semisegmented APCNs with polyMMA arms with degrees of polymerization (DPs) of 10, 20, 30, and 40 and three with polyDMAEMA arms with DPs of 10, 20, and 30 were prepared. The sol fraction extracted from the APCNs, the percentage of linear polymer in the sol fraction, and the molecular weights of the branched fraction of the extractables increased as the DP of the arms increased. The degrees of swelling (DSs) in water of all semisegmented APCNs increased with decreasing pH and increasing percentage of DMAEMA hydrophilic units. Despite the rather imperfect, semisegmented placement of the dissimilar units, extensive small-angle neutron scattering (SANS) experiments in D2O indicated that nanophase organization did take place within these APCNs and persisted, in many cases, even at full ionization of the hydrophilic monomer repeating units. The SANS profiles were also used to calculate the spacings between the scattering centers, which were found to increase with the content in the DMAEMA units and their degree of ionization. © 2009 American Chemical Society. 42 8 2972 2980 Cited By :24

A binol ester initiator was used as a bifunctional ATRP initiator in combination with PMDETA/copper bromide catalyst system in DMF to synthesize n-butyl acrylate macroinitiator at 50� C. The resulting macroinitiator was used for a detailed investigation of the ATRP of methyl methacrylate (MMA) with CuCl/N,N,N?,N?,N?-pentamethyldiethylenetriamine (PMDETA) catalyst system in anisole at 30� C. Thus, the MMA polymerization is shown to proceed with first order kinetics, with predicted molecular weight and narrow polydispersity indices. Gel permeation chromatography (GPC) and NMR were used for the characterization of the polymers synthesized. Copyright ? Taylor & Francis, Inc.

We present two novel, homologous, pyridine-based monomers, 2-(pyridin-2-yl)ethyl methacrylate (PyEMA) and (pyridin-2-yl)methyl methacrylate (PyMMA), which, despite their structural similarity, the former can be readily thermolyzed to methacrylic acid, while the latter remains intact under the same conditions. This was most dramatically demonstrated in the present work, where PyEMA and PyMMA were randomly terpolymerized with a dimethacrylate cross-linker using reversible addition-fragmentation chain transfer polymerization to yield weakly double-cationic polyelectrolyte hydrogels of three different compositions which, upon thermal treatment, they were readily converted to polyampholyte hydrogels. While the parent double-cationic polyelectrolyte hydrogels exhibited a swelling response only to low-pH conditions, the daughter polyampholyte hydrogels presented swelling responses to both high- and low-pH conditions. Owing to the relative values of the effective pKa's of the weakly acidic and weakly basic units, with the latter being lower than the former ("inverse polyampholyte" behavior), the swelling profiles of the daughter hydrogels were insensitive to polyampholyte composition. © 2014 American Chemical Society. 47 5 1819 1827 Cited By :11

In this communication, we show that 2-(pyridin-2-yl)ethanol is a good protecting group for methacrylic acid (MAA), which can be selectively removed, after polymerization, either chemically under alkaline conditions or thermally at or above 110°C, while it is stable under acidic conditions and resists catalytic hydrogenolysis. To this end, the monomer 2-(pyridin-2-yl)ethyl methacrylate was synthesized, purified, and homo- and co-polymerized via two controlled polymerization methods, group transfer polymerization (GTP) and reversible addition-fragmentation chain transfer (RAFT) polymerization, to obtain homopolymers and diblock copolymers with methyl methacrylate (GTP) and styrene (RAFT), whose 2-(pyridin-2-yl)ethyl groups could be readily cleaved by chemical or thermal treatment, yielding diblock copolymers with polyMAA segments. The 2-(pyridin-2-yl)ethyl protecting group is one of the very few moieties that can be hydrolyzed under alkaline conditions, and, owing to the commercial availability and relatively low cost of 2-(pyridin-2-yl)ethanol, the present group is expected to find extensive use by the polymer community. © The Royal Society of Chemistry 2012. 3 12 3228 3231 Cited By :15

Isobornyl methacrylate (IBMA), a bulky hydropho- bic methacrylate, undergoes very fast polymerization, in bulk, with Cu(I)Br/N,N,N 0 ,N 00 ,N 00 -pentamethyldiethylenetriamine (PMDETA)/ethyl-2-bromoisobutyrate system, at ambient tem- perature. IBMA also undergoes a spontaneous initiator-free polymerization, at ambient temperature, with Cu(I)Br/PMDETA catalytic system in dimethyl sulfoxide-water mixtures. The rate of the polymerization is seen to increase with the water con- tent up to 80 mol % of water. A possible intervention of air in initiation is proposed. The active Cu(0) formed by the dispro- portionation of Cu(I) species in aqueous medium probably plays a vital role for a possible air-initiation of IBMA via single electron transfer-living radical polymerization (SET-LRP) mech- anism. A high tolerance level to water under SET-LRP condi- tions is demonstrated. The poly(IBMA) samples obtained exhibit low molecular weight distributions (1.1-1.3). Simi- lar behavior was not observed with other common methacry- lates such as methyl methacrylate, t-butyl methacrylate, cyclohexyl methacrylate, and benzyl methacrylate. V C 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 49: 2165-2172, 2011

A novel initiator containing pyrene, a fluorescent moiety, was prepared by reacting 1-aminopyrene and 2-bromoisobutyl bromide. The structure elucidation of the new initiator was carried out using various spectroscopic tools, as well as through single crystal X-ray diffraction studies. Novel, fluorescent amphiphilic block copolymers with a pyrene end-group, poly(styrene-b-acrylic acid) [P(S-b-AA)], poly(methyl methacrylate-b-dimethylaminoethyl methacrylate) [P(MMA-b-DMAEMA)], poly(styrene-b-tert-butyl acrylate) [P(S-b-t-BA)], poly(styrene-b-dimethylaminoethyl methacrylate) [P(S-b-DMAEMA)] were successfully synthesized by the atom transfer radical polymerization (ATRP) method, using CuBr as the catalyst and N,N,N?,N?,N?- pentamethyldiethylenetriamine (PMDETA)/N,N,N?,N?,N?- hexamethyltriethylenetetramine (HMTETA) as the complexing agent. The polymers were characterized by GPC, 1H-NMR, IR and UV-Vis spectroscopies. It was observed that as the polymerization time increased, both the conversion and the molecular weight increased linearly with time. The fluorescence properties of the polymers prepared were recorded. The physical properties and especially the pH dependent swelling properties of the amphiphilic block copolymers have been investigated. The utility of the block copolymers in the formation of stable dispersion of cadmium sulphide nanoparticles was investigated as a model study. Copyright � Taylor & Francis Group, LLC.

Three series of conetworks based on cross-linked star polymers of different architectures were prepared using group transfer polymerization. The first series of conetworks were amphiphilic, based on the hydrophobic monomer benzyl methacrylate and the ionizable hydrophilic 2-(dimethylamino)ethyl methacrylate (DMAEMA) the second series were double-hydrophobic, based on methyl methacrylate and n-butyl methacrylate the third series were ampholytic, based on the negatively ionizable methacrylic acid (MAA) and the positively ionizable DMAEMA. The MAA units were introduced into the conetworks via the polymerization of tetrahydropyranyl methacrylate followed by its acid hydrolysis after network formation. All the precursors to the conetworks were characterized in terms of their molecular weights using gel permeation chromatography. The degrees of swelling (DSs) of all the conetworks were measured as a function of pH or in a mixture of solvents. Moreover, the effect of the architecture of the conetworks on the DS was investigated. The DS was found to be influenced more by the charge density of the conetwork than by the compatibility with the solvent, and more by the solvent compatibility than by the architecture of the conetwork. Copyright © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. 291-292 1 36 42 Cited By :6

Four linear amphiphilic multiblock copolymers based on 2-(dimethylamino) ethyl methacrylate (DMAEMA, hydrophilic) and methyl methacrylate (MMA, hydrophobic), bearing from two to five blocks, were synthesized using reversible addition - fragmentation chain transfer polymerization and stepwise monomer additions. The degree of polymerization of each hydrophilic poly DMAEMA block was ~50, while that of the hydrophobic polyMMA blocks was ca. 20. The stepwise monomer addition procedure secured that each higher multiblock was composed of its immediately lower homologue plus exactly one extra block. The molecular weights (MW) of the synthesized (co)polymers, as measured by gel permeation chromatography (GPC), were close to the theoretically expected. GPC also indicated rather narrow molecular weight distributions which, however, broadened with the number of blocks. The compositions of the copolymers, as determined by proton nuclear magnetic resonance spectroscopy, were also close to the expected values. The cloud points of the copolymers, measured by turbidimetry, were found to increase with the number of blocks. The sizes of the micelles formed by the copolymers in aqueous solution were characterized using dynamic light scattering and small-angle neutron scattering. The determined values of the hydrodynamic radii, the radii of gyration, and the aggregation numbers of the micelles increased slightly with the block number from the triblock to the pentablock copolymer, implying extensive folding of the chains of the tetrablock and the pentablock copolymers in their micelles. The aggregation number of the tetrablock copolymer was approximately one-half that of the diblock copolymer whose unimer MW was onehalf that of the tetrablock, suggesting that the micellar cores of these two types of micelles were composed of the same number of hydrophobic units. © 2010 American Chemical Society. 43 6 2713 2720 Cited By :33

Tetrahydrofurfuryl methacrylate (THFMA), a heterocyclic monomer was polymerized by ambient temperature Atom Transfer Radical Polymerization (AT ATRP) using CuX/PMDETA/EBiB system. THFMA was found to undergo very rapid polymerization, in bulk. For a target DP > 200, bulk polymerization results in cross-linking as evidenced by (CH2)n,wag peaks (IR spectroscopy). Atom Transfer Radical copolymerization (ATRcP) of THFMA with MMA was performed and the reactivity ratios were calculated from the copolymer composition, as determined by 1H NMR, using Fineman-Ross and Kelen-Tudos methods. The reactivity ratios determined for ATRP were found to be significantly different from the literature values for conventional free radical polymerization (CFRP). This may be due to the coordination of copper catalytic system with the oxygen atom of the tetrahydrofurfuryl group that could lead to the variation in reactivity ratios. 1H NMR evidence for catalyst-monomer interaction is also provided. � 2009 Elsevier Ltd. All rights reserved.

Five linear amphiphilic multiblock copolymers based on 2-(dimethylamino) ethyl methacrylate ("D") and methyl methacrylate ("M"), bearing from two to six blocks, were synthesized using sequential group transfer polymerization. All copolymers were obtained from the same polymerization flask (by the withdrawal of a sufficient amount of sample and appropriate adjustment of subsequent monomer loadings) to ensure better comparison between the various multiblocks. A theoretical degree of polymerization (DPth) of 20 was targeted for all D blocks, whereas a DPth of 10 was aimed for the M blocks. Upon characterization using gel permeation chromatography and H NMR spectroscopy, the copolymers were confirmed to have the expected values of molecular weights and compositions. Subsequently, the aqueous micellization behavior of these copolymers was probed using dye solubilization, dynamic light scattering, and small-angle neutron scattering. Dye solubilization experiments indicated that micelles readily formed at low copolymer concentrations equal to or less than 0.03% w/w. The scattering measurements revealed that despite the differences in their overall DPth values, the triblock, the tetrablock, and the pentablock copolymers selfassembled in water to form micelles with radii of gyration and hydrodynamic radii very similar to each other, suggesting chain looping and the formation of flowerlike micelles, which is in agreement with recent Monte Carlo simulations. © 2009 American Chemical Society. 42 15 5492 5498 Cited By :28

Mixtures of two cleavable dimethacrylate crosslinkers, the hydrolyzable di(methacryloyloxy-1-ethoxy)methane (DMOEM) and the thermolyzable 1,1-ethylenediol dimethacrylate (EDDMA), were used for the preparation of neat crosslinker polymer networks, randomly crosslinked polymer networks of methyl methacrylate (MMA), and star polymers of MMA, using group transfer polymerization in tetrahydrofuran (THF). All star polymers and randomly crosslinked polymer networks containing mixtures of the hydrolyzable DMOEM and the thermolyzable EDDMA crosslinkers gave THF-soluble final products when subjected to sequential thermolysis and hydrolysis, in this order. When applying sequential hydrolysis and thermolysis, only the star polymers with an EDDMA crosslinker content equal to or higher than 50% gave THF-soluble final products. © 2009 Wiley Periodicals, Inc. 47 21 5853 5870 Cited By :1

Polyethylene glycol) (PEG)-containing quasi-model amphiphilic polymer conetworks (APCNs) were prepared by reversible addition fragmentation chain transfer (RAFT) polymerization using α,ω-bis(2-cyanoprop-2-yl dithiobenzoate)-PEG as a bifunctional RAFT macrochain transfer agent (macro-CTA) and stepwise additions of a hydrophobic monomer and a crosslinker (crosslinker: macro-CTA = 10:1, reaction time 24 h). Three different types of monomers, methyl methacrylate (MMA), n-butyl acrylate and styrene, were employed as the hydrophobic monomers, whereas ethylene glycol dimethacrylate, ethylene glycol diacrylate and 1,4-divinylbenzene served as the respective crosslinkers. PEG homopolymer hydrophilic quasi-model networks were also prepared by RAFT-polymerizing the three crosslinkers directly onto the two active ends of the PEG-based macro-CTA. From the three ABA triblock copolymers prepared, the MMA-containing one was obtained at the highest polymerization yields. The crosslinking yields of the three ABA triblock copolymers with the corresponding crosslinkers were higher than those of the PEG-based macro-CTA with the same crosslinkers. The degrees of swelling (DSs) of all conetworks were measured in water and in tetrahydrofuran (THF). The DSs of the APCNs in THF were higher than those in water, whereas the reverse was true for the DSs of the hydrophilic homopolymer networks. Finally, the aqueous DSs of the APCNs were lower than those of the corresponding hydrophilic homopolymer networks. © 2008 Wiley Periodicals, Inc. 46 22 7556 7565

The surface-initiated ATRP of benzyl methacrylate, methyl methacrylate, and styrene from magnetite nanoparticle is investigated, without the use of sacrificial (free) initiator in solution. It is observed that the grafting density obtained is related to the polymerization kinetics, being higher for faster polymerizing monomer. The grafting density was found to be nearly 2 chains/nm2for the rapidly polymerizing benzyl methacrylate. In contrast, for the less rapidly polymerizing styrene, the grafting density was found to be nearly 0.7 chain/nm2. It is hypothesized that this could be due to the relative rates of surface-initiated polymerization versus conformational mobility of polymer chains anchored by one end to the surface. An amphiphilic diblock polymer based on 2-hydroxylethyl methacrylate is synthesized from the polystyrene monolayer. The homopolymer and block copolymer grafted MNs form stable dispersions in various solvents. In order to evaluate molecular weight of the polymer that was grafted on to the surface of the nanoparticles, it was degrafted suitably and subjected to gel permeation chromatography analysis. Thermogravimetric analysis, transmission electron microscopy, and Fourier transform infrared spectroscopy were used to confirm the grafting reaction.