Synthesis of monodisperse polymers from proteins

Proteins are functional biopolymers; viewed as molecules, they are also monodisperse polyamides with chemically reactive side chains. This paper describes the use of proteins as starting materials for the synthesis of monodisperse polymers with nonbiological functionalities attached to the side chains. It demonstrates the complete derivatization of amine groups (lysine side chains and N-termini) on three different proteins by addition of activated carboxylate reagents in aqueous solutions containing sodium dedecyl sulfate (SDS), under denaturing conditions. Several different acylating reagents were used to generate derivatized proteins; the resulting compounds constitute a new class of monodisperse, semisynthetic polymers, having the potential for wide variation in the structure of the backbone and of the side chains. Modification of lysozyme on a gram scale demonstrated that the method can generate useful quantities of material.     

Liquid-Crystalline Polyurethanes. 5. Polyurethanes Containing the Cholesterol Moiety in the Side Chain

In the preceding papers of this series, we reported the synthesis of liquid-crystalline polyurethanes containing mesomorphic moieties in the main chain and in side chains [1–4]. Liquid crystalline polymers with side groups containing the cholesterol moiety have also been studied [5, 6]. The main focus of attention has centered around the study of phase transitions of acrylic and methacrylic derivatives of cholesterol. This paper describes the synthesis of a new type of liquid-crystalline polyurethane containing the cholesterol moiety in side chains.     

Poly(arylene oxides) containing sulfo acid groups: Synthesis, properties, and application

Key advances in the synthesis, characterization, and application of poly(arylene oxides) containing sulfo acid groups in main chains of macromolecules and side substituents are surveyed. The main advantages and drawbacks of various approaches to the synthesis of these polymers, such as postsulfonation of poly(arylene oxides), polycondensation with the use of sulfonated monomers, and transformations of polymers containing reactive groups, are analyzed.     

Discotic liquid-crystalline side chain polymers with inositol derivatives as mesogens

The synthesis of monofunctionalized myo- and scyllo-inositol derivatives and their attachment as side groups on a polysiloxane backbone are described. All polymers with scyllo-inositol mesogens show liquid-crystalline behaviour. In contrast to this the myo-inosital mesogens containing polymers exhibit no liquid-crystalline phases.     

Dendronized polymers via Diels–Alder “click” reaction

A modular approach toward the synthesis of polymers containing dendron groups as side chains is developed using the Diels–Alder “click” reaction. For this purpose, a styrene‐based polymer appended with anthracene groups as reactive side chains was synthesized. First through third‐generation polyester dendrons containing furan‐protected maleimide groups at their focal point were synthesized. Facile, reagent‐free, thermal Diels–Alder cycloaddition between the anthracene‐containing polymer and latent‐reactive dendrons leads to quantitative functionalization of the polymer chains to afford dendronized polymers. The efficiency of this functionalization step was monitored using ¹H and ¹³C NMR spectroscopy and FTIR and UV–vis spectrometry. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 410–416, 2010     

Properties of dendronized acrylic polymers: Effect of composition and structure of peripheral groups

Two series of new acrylic polymers carrying L-aspartic acid-based dendrons in side chains with terminal hexyloxycarbonyl groups that are both directly and indirectly, via a rigid spacer, attached to polymer chains have been synthesized by the free-radical polymerization of monomers. The polymerization ability of the monomers has been studied. The properties of new polymers are compared with the properties of polymer analogs containing terminal methoxycarbonyl groups of dendrons. Upon incorporation of the rigid spacer, the shielding of reactive centers decreases and the polymerizability of the monomers increases. The replacement of terminal methyl groups in dendrons with hexyl groups in spacer-free polymers leads to a reduction in the degree of polymerization, while in the case of polymers containing spacers, high-molecular-mass products arise. This phenomenon is facilitated by the amphiphilic nature of the polymers and the additional enhancement in the rigidity of chains. A polymer carrying a third-generation dendron has been synthesized only for the latter series.     

New amphiphilic polyacrylamides: Synthesis and characterisation of pseudo-micellar organisation in aqueous media

In order to offer new tools for developing structure-property relationships for intramolecular associative polymers (polysoaps), the synthesis of three families of comb-like amphiphilic cationic polymers with great structure variability is described. These polymers with amphiphilic repeating units are polyacryl or methacrylamides laterally substituted by a group containing a quaternary ammonium site and a hydrophobic alkyl side chain with 10-16 carbon atoms. Two complementary synthesis methods were developed successfully. In the first method, the tertiary amine groups of neutral polymer precursors were quaternised with various n-alkyl bromides. Five polymers were obtained in this way. On the contrary, the second method consisted of synthesizing first amphiphilic cationic acryl or methacrylamide monomers. The 11 monomers thus obtained were then polymerised by conventional free radical polymerisation in solution. The polymers obtained by both methods only differed in their molecular weights, the second method leading to much higher molecular weights (up to 2 × 10⁶ g/mol). A preliminary investigation of the properties of a few of these polymers in solution showed interesting amphiphilic behaviour. The variation of the reduced viscosity of hydro-methanolic polymer solutions with polymer concentration revealed a strong intramolecular macromolecular folding. The microdomains corresponding to the intramolecular association of the hydrophobic alkyl side chains were eventually characterised by pyrene fluorescence spectroscopy. The local polarity of the pyrene probe was considerably lowered with respect to that of the surrounding aqueous phase and was dependent upon the macromolecular structure of the amphiphilic cationic polymers.     

Inorganic coordination polymers. XVI. Zinc(II) phosphinate polymers containing polyphenylene and poly(phenylene oxide) side groups

The synthesis and characterization of a series of new phosphinic acids and the zinc polymers prepared from them are reported. These compositions are characterized by the presence of short polyphenylene and poly(phenylene oxide) chains as side groups. Some of the zinc derivatives were found to be tractable polymers with good thermal stability.     

Novel nonionic surfactants based on sulfoxides. 2. Homo- and copolymers

The synthesis of new nonionic amphiphilic polymers of the polysoap type is described, as well as their general behaviour in aqueous solution. The polymers were prepared by homopolymerisation of acrylate polymerisable surfactants (or "surfmers"), which bear the nonionic sulfoxide moiety. Alternatively, small hydrophilic acrylate and acrylamide monomers bearing the nonionic sulfoxide moiety were copolymerised with dodecylacrylate and N-dodecyl- N-methylacrylamide. Compared to many other nonionic hydrophilic fragments, a single sulfoxide group behaves as a strongly hydrophilic fragment of small volume. However, its relative hydrophilicity depends sensitively on its precise positioning in the polymers. Properly placed, three sulfoxide groups can balance up to two dodecyl chains to obtain still water-soluble polymers that exhibit typical polysoap properties. Some of the new nonionic polymers show lyotropic liquid-crystalline behaviour at ambient temperature.     

Synthesis and Properties of Polymers Containing Phosphatidylcholine Analogues in the Main Chains and Long Alkyl Groups in the Side Chains

Abstract

Several new polymers containing hydrophilic phosphatidylcholine analogues in the main chains and hydrophobic docosyl or stearyl groups in the side chains have been synthesized. The polymers exhibit thermotropic liquid crystalline behaviors from 65°C up to ca. 280°C as determined by polarizing microscopy. One of the polymers shows slight crystallinity as evidenced by wide-angle x-ray diffraction. The viscosity measurements show that some of the polymers have properties similar to usual polyelectrolytes. However, one polymer shows a linear increase of reduced viscosity.     

Complex macromolecular structures from stable radical containing block copolymers

A novel synthetic strategy for the synthesis of graft copolymers is reported. Block copolymers containing segments with stable nitroxyl radicals side groups were first prepared by anionic polymerization, which were then used as a precursor for the subsequent nitroxide-mediated radical polymerization (NMRP) of styrene. This way, block–graft copolymers with polystyrene side chains grafted from one of the blocks were successfully synthesized in a controlled manner. In addition, block–graft copolymers with grafted polystyrene chains and a poly(tert-butyl methacrylate) block were subjected to hydrolysis to yield the corresponding amphiphilic polymers. The structures and the molecular weight characteristics of the polymers were characterized by spectral and chromatographic analyses. The surface morphology of thus obtained polymers was also investigated by microscopic techniques. © 2019 Wiley Periodicals, Inc. J. Polym. Sci. 2020 , 58, 62–69     

Catalytic reactions of oxetanes with protonic reagents and aprotic reagents leading to novel polymers

This paper reports new addition reactions of oxetanes with certain protonic reagents such as carboxylic acid, phenol, and thiol, and with certain aprotic reagents such as acyl chloride, thioester, phosphonyl dichloride, silyl chloride, and chloroformate using quaternary onium salts as catalysts. The kinetic study of the addition reactions of oxetanes was also investigated. These new addition reactions were applicable to the synthesis of new polymers. These polyaddition systems could also construct both polymer main chains and reactive side chains. The alternating copolymerization of oxetanes with carboxylic anhydride was performed. Furthermore, it was found that anionic ring‐opening polymerization of oxetanes containing hydroxy groups proceeded to afford the hyperbranched polymer (HBP) with an oxetanyl group and many hydroxy groups at the ends of the polymer chains. Alkali developable photofunctional HBPs were synthesized by the polyaddition of bis(oxetane)s or tris(oxetane)s, and their patterning properties were examined, too. The photo‐induced cationic polymerization of the polymers with pendant oxetanyl groups and the thermal curing reactions of polyfunctional oxetanes (oxetane resins) were also examined to give the crosslinking materials quantitatively. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 709–726, 2007     

Towards a universal polymer backbone: design and synthesis of polymeric scaffolds containing terminal hydrogen-bonding recognition motifs at each repeating unit

Polymers containing terminal hydrogen-bonding recognition motifs based on diaminotriazine and diaminopyridine groups in their side chains for the self-assembly of appropriate receptors have been prepared by ring-opening metathesis polymerization (ROMP) of norbornenes. A new synthetic method for the preparation of norbornene monomers based on pure alkyl spacers is introduced. These monomers show unprecedented high reactivity using ROMP. To suppress self-association of diaminotriazine-based polymers, polymerizations were run in presence of N-butylthymine. The butylthymine acts as a protecting group via self-assembly onto the hydrogen-bonding sites of the polymeric scaffold, thereby solubilizing the polymer. Diaminopyridine monomers do not require the presence of a protecting group due to their low propensity to dimerize. In addition, they exhibit a high affinity for hydrogen-bonded receptors on both monomeric and polymeric level. These polymers present our first building blocks towards the design and synthesis of a "universal polymer scaffold".     

Synthesis of N-substituted polyethylenimines with polarizable side chain pendent groups

Two new N-substituted polyethylenimines containing carbazole and acridone groups on the side chains were prepared. The polymers were obtained by cationic ring opening polymerization of the corresponding 2-oxazoline monomers. The carbazole containing oxazoline was low melting and could be polymerized in bulk; however the acridone containing monomer had a high melting point and solution polymerization had to be used. This paper describes the synthetic procedures used to obtain these polymers.     

Thermotropic liquid-crystalline comb-like polymers with polyacrylamide main chain—I. Synthesis and mesomorphic structures of polymers with lipobiphenyl side chains

The synthesis of polymerizable lipobiphenyls, the study of the kinetics of their radical polymerization giving comb-like polymers, and the study of the thermotropic behaviour of the polymers are reported. Utilization of all the information provided by X-ray diffraction diagrams showed that polymers with polyacrylamide main chains and lipobiphenyl side chains exhibit successively, between room temperature and isotropization temperature, two mesophases: an ordered tilted double layer smectic phase SI2, and a disordered tilted double layer smectic phase SC2.     

Synthesis of side chain liquid-crystalline polysiloxane containing trans-cyclohexane-based mesogenic side groups

The synthesis and characterization of nine new side chain liquid-crystalline polysiloxanes containing one cyclohexyl ring and another 2-4 aromatic rings in their mesogenic side groups are described. All synthesized polymers displayed nematic mesomorphism. Most of the polymers showed a very wide mesomorphic temperature range. The mesogenic core length has profound influence on the phase transitions of the polymers. The mesomorphic temperature range increased with increasing mesogenic core length.     

Poly(perylene‐alt‐phenyleneethynylene)s with multiple pendant ester groups in various lengths: Synthesis,photophysics and selective hydrolysis

Five fluorescence polymers with poly(perylene‐alt‐phenyleneethynylene)s (PPPEs) backbone and multiple side chains containing ester‐groups were synthesized via Sonogashira coupling reaction. These polymers were soluble in common organic solvents to form red‐orange solution. The polymer powders had dark red color. The absorption/emission spectra of these polymers were similar, with absorption bands between 300 and 600 nm and an emission peak between 520 and 700 nm. Furthermore, the ester groups of the side chains were partially or completely hydrolyzed, resulting in the fluorescence PPPEs with tunable density of carboxylic acid functional groups on the polymer chains as interaction/reaction sites for further applications. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 1880–1886     

Synthesis and properties of poly(acrylamide)s containing both long chain alkyl groups and phosphatidylcholine analogues in the side chains

A series of new phospholipid analogous acrylamide monomers ( 4a–e ) containing long alkyl chains as hydrophobic groups and containing phosphatidylcholine analogues as hydrophilic group were synthesized in high yields. The homopolymerizations and copolymerization ( 4b with 4e ) were carried out in the presence of a radical initiator. The structures and thermal properties of these polymers were investigated by x-ray diffraction analysis, DSC, and polarizing microscopy measurements. It has been revealed that these homopolymers ( 5b, 5c , and 5d ) which bear saturated long-hydrocarbon chains in the side chains exhibited not only orderly stacked bilayer structures at room temperature but also clear liquid crystalline behavior within a wide temperature range. The viscosity behavior of all polymers was found similar to usual polyelectrolytes in porlar solvent. The polymers obtained were also characterized by ¹H-NMR, IR, and melting point, respectively. © 1996 John Wiley & Sons, Inc.     

Recent Progress in the Preparation of Functional Methacrylate Polymers

Application of anionic polymerization and group transfer polymerization to the synthesis of methacrylate polymers with one or two functional endgroups and with functional groups in the side chain is described. Success in the preparation of end-functional polymers depends largely on the absence of chain transfer and chain termination reactions. The higher stability of living chains in group transfer polymerization at temperatures as high as 100°C makes it the preferred route to functional polymers.     

Synthesis of side chain liquid-crystalline polysiloxane containing trans-cyclohexane-based mesogenic side groups

Abstract

The synthesis and characterization of nine new side chain liquid-crystalline polysiloxanes containing one cyclohexyl ring and another 2-4 aromatic rings in their mesogenic side groups are described. All synthesized polymers displayed nematic mesomorphism. Most of the polymers showed a very wide mesomorphic temperature range. The mesogenic core length has profound influence on the phase transitions of the polymers. The mesomorphic temperature range increased with increasing mesogenic core length.