Density functional theory, DFT, PBE1PBE functional and 6-31+G(d,p) basis set in Gaussian 03 software were used in order to determine the reactivity order of the R group in RAFT agents used in the radical addition-fragmentation transfer polymerization, through the evaluation of reactivity parameters such as: global and local electronegativity, hardness, softness, and philicity. It was found that the reactivity order is governed by both the number and the composition of the substituent group (primary, secondary or tertiary); that is, the larger those parameters are the larger factors like steric hindrance, polar effects and electronic interchanges are, which favors the breaking of the C-S bond from the adduct radical, permitting the exit of the leaving radical and allowing, as a consequence, the fragmentation step in RAFT polymerization. Trisubstituted dithioesters with structure S = C(Z)S-R, where Z = Phenyl and R = C(CH(3))(2)CONH(2), C(CH3)2Ph or (CH(3))(2)C(6)H(8)OCH(3), in accordance with the previously exposed, presented the most favorable reactivity parameters.
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http://dx.doi.org/10.1007/s00894-009-0524-z | DOI Listing |
Analyst
January 2025
Key Laboratory of Phytochemistry and Natural Medicines, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China.
Although the glycosylation of viral proteins plays a critical role in the process of viral invasion into host cells, studies on the glycosylation of monkeypox virus (MPXV) structural proteins have not yet been reported. To investigate the importance of MPXV protein glycosylation, poly Ser-Arg (poly SR) materials capable of simultaneously enriching both -glycopeptides and -glycopeptides were synthesized by surface-initiated reversible addition-fragmentation chain transfer (SI-RAFT) polymerization. The poly SR materials were evaluated using the digest mixture of standard proteins containing bovine fetuin and bovine serum albumin, and the digest of complex biological samples including bovine sperm tail lysate, mouse sperm tail lysate, mouse brain lysate, and human serum.
View Article and Find Full Text PDFMacromolecules
January 2025
Department of Chemistry and Biochemistry, Miami University, 651 E High St, Oxford, Ohio 45056, United States.
Photochemical processes are often thought to be temperature-independent. However, photochemical polymerization involves photochemical processes such as light-driven radical generation coupled with thermal-driven reactions such as monomer propagation. The apparent activation energy of propagation, ( ), of a series of three monomers, methyl acrylate (MA), methyl methacrylate (MMA), and styrene (STY), are deduced from Arrhenius analysis of conventional and RAFT photopolymerization of these monomers across a range of corresponding temperatures.
View Article and Find Full Text PDFPolym Chem
January 2025
Department of Chemistry and Polymer Science, Stellenbosch University Matieland 7602 South Africa
Poly(styrene--maleic anhydride) (SMAnh) is a petroleum-based copolymer with desirable properties that afford utility in both industrial and academic fields. The reversible addition-fragmentation chain transfer (RAFT)-mediated polymerization of the bioderived comonomers, indene and itaconic anhydride, was explored using three chain transfer agents with varying activity, and generally well-controlled ( < 1.40) polymerizations were observed.
View Article and Find Full Text PDFChem Sci
January 2025
Université Paris-Saclay, CNRS, Institut Galien Paris-Saclay 91400 Orsay France +33-180006081.
The synthesis of degradable polymer prodrug nanoparticles is still a challenge to be met, which would make it possible to remedy both the shortcomings of traditional formulation of preformed polymers (, low nanoparticle concentrations) and those of the physical encapsulation of drugs (, burst release and poor drug loadings). Herein, through the combination of radical ring-opening polymerization (rROP) and polymerization-induced self-assembly (PISA) under appropriate experimental conditions, we report the successful preparation of high-solid content, degradable polymer prodrug nanoparticles, exhibiting multiple drug moieties covalently linked to a degradable vinyl copolymer backbone. Such a rROPISA process relied on the chain extension of a biocompatible poly(ethylene glycol)-based solvophilic block with a mixture of lauryl methacrylate (LMA), cyclic ketene acetal (CKA) and drug-bearing methacrylic esters by reversible addition fragmentation chain transfer (RAFT) copolymerization at 20 wt% solid content.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
School of Chemistry and Chemical Engineering, Shandong University, Jinan, 250100, China.
In this contribution, we designed a new xanthate RAFT agent by introducing (5,6,7,8-tetrahydro-2-naphthalenyl)oxy (TNO) as the Z group, namely 2-[(((5,6,7,8-Tetrahydro-2-naphthalenyl)oxycarbonothioyl)thio)ethyl propanoate] (TNXEP). Due to the presence of the TNO group, TNXEP enabled highly controlled and ultrafast photoiniferter RAFT polymerization under violet (λ=405 nm) and blue (λ=450 nm) light. This approach was effectively extended to aqueous media for polymerization-induced self-assembly (PISA), facilitating the synthesis of polymeric nanoparticles.
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