Synthesis and characterization of amphiphilic diblock copolymer of polystyrene and polyvinyl alcohol using ethanolaminebenzophenone as photochemical binary initiation system.

ABSTRACT: Amphiphilic diblock copolymers of polyvinyl alcohol (PVA) and polystyrene (PS), which are very difficult to prepare by common polymerization methods, have been obtained by initiation of the polymerization of styrene and vinyl acetate successively, followed by hydrolysis, using the ethanolamine-benzophenone (BP) charge-transfer complex (CTC). The effects of solvents, concentration of monomer, BP, ethanolamine, and PS prepolymer, with a reactive imino group (PS a ), on the photo-induced chargetransfer polymerization (CTP) of St and block copolymerization of VAc are discussed. The copolymer of PS-b-PVAc and the hydrolyzed product, PS-b-PVA, were characterized by FTIR, NMR, and GPC in detail. The effect of PS chain length on the crystallization of PVA was described

Copolymerization of the Macromonomer Poly(ethylene oxide) with Styryl End Group and Styrene in the Presence of Poly(-caprolactone) with 2,2,6,6- Tetramethylpiperidinyl-1-oxy End Group by Controlled Radical Mechanism

ABSTRACT: A copolymerization of macromonomer poly(ethylene oxide) (PEO) with a styryl end group (PEO S ) and styrene was successfully carried out in the presence of poly(-caprolactone) (PCL) with 2,2,6,6-tetramethylpiperidinyl-1-oxy end group (PCL T ). The resulting copolymer showed a narrower molecular weight distribution and controlled molecular weight. The effect of the molecular weight and concentration of PCL T and PEO S on the copolymerization are discussed. The purity of PEO S exerted a significant effect on the copolymerization; when the diol contents of PEO macromonomer were greater than 1%, the crosslinking product was found

Synthesis of Well-Defined, Brush-Type, Amphiphilic [Poly(styrene-co-2-hydroxyethyl methacrylate)-graft- Poly(e-caprolactone)]-b-Poly(ethylene oxide)-b- [Poly(styrene-co-2-hydroxyethyl methacrylate)-graft- Poly(e-caprolactone)] and Its Aggregation Behavior

ABSTRACT: Brush-type, amphiphilic [poly(styrene-co-2-hydroxyethyl methacrylate)-graft-poly(e-caprolactone)]-b-poly(ethylene oxide)-b-[poly(styrene-co-2-hydroxyethyl methacrylate)-graft-poly(e-caprolactone)] was successfully synthesized via consecutive ringopening anionic polymerization, reversible addition-fragmentation chain transfer (RAFT) polymerization, and coordination-insertion ring-opening polymerization (ROP). Two poly (ethylene oxide) macro-RAFT agents with two 3-benzylsulfanylthiocarbonylsufanyl propionic acid end groups were prepared by the reaction of Poly(ethylene oxide) with hydroxyl group at two ends [HO-PEO-OH] with 3-benzylsulfanylthiocarbonylsufanyl propionic acid chloride in the presence of pyridine; their molecular weights were 4840 and 8570 g/mol, and their molecular weight distributions were 1.07 and 1.09, respectively. The obtained macro-RAFT agents were used to mediate the copolymerization of styrene and 2-hydroxyethyl methacrylate with 2,2-azobisisobutyronitrile as the initiator and dimethylformamide as the solvent. The hydroxyl groups of the 2-hydroxyethyl methacrylate units of the resulting triblock copolymers then initiated the ROP of e-caprolactone in the presence of Sn(Oct) 2 at 100 8C in toluene. It was determined that the RAFT process was controllable. The self-assembled morphologies of the copolymers varied from rods to pearl necklaces and vesicles with an increase in the water concentration in tetrahydrofuran from 22.0 to 25.7, 29.6, and 39.0%, and the morphologies were also dependent on the molecular weight and chain structure of the copolymers

Key candidate genes and pathways in T lymphoblastic leukemia/lymphoma identified by bioinformatics and serological analyses

T-cell acute lymphoblastic leukemia (T-ALL)/T-cell lymphoblastic lymphoma (T-LBL) is an uncommon but highly aggressive hematological malignancy. It has high recurrence and mortality rates and is challenging to treat. This study conducted bioinformatics analyses, compared genetic expression profiles of healthy controls with patients having T-ALL/T-LBL, and verified the results through serological indicators. Data were acquired from the GSE48558 dataset from Gene Expression Omnibus (GEO). T-ALL patients and normal T cells-related differentially expressed genes (DEGs) were investigated using the online analysis tool GEO2R in GEO, identifying 78 upregulated and 130 downregulated genes. Gene Ontology (GO) and protein-protein interaction (PPI) network analyses of the top 10 DEGs showed enrichment in pathways linked to abnormal mitotic cell cycles, chromosomal instability, dysfunction of inflammatory mediators, and functional defects in T-cells, natural killer (NK) cells, and immune checkpoints. The DEGs were then validated by examining blood indices in samples obtained from patients, comparing the T-ALL/T-LBL group with the control group. Significant differences were observed in the levels of various blood components between T-ALL and T-LBL patients. These components include neutrophils, lymphocyte percentage, hemoglobin (HGB), total protein, globulin, erythropoietin (EPO) levels, thrombin time (TT), D-dimer (DD), and C-reactive protein (CRP). Additionally, there were significant differences in peripheral blood leukocyte count, absolute lymphocyte count, creatinine, cholesterol, low-density lipoprotein, folate, and thrombin times. The genes and pathways associated with T-LBL/T-ALL were identified, and peripheral blood HGB, EPO, TT, DD, and CRP were key molecular markers. This will assist the diagnosis of T-ALL/T-LBL, with applications for differential diagnosis, treatment, and prognosis

Copolymerization of Styrene and Vinyl Acetate by Successive Photoinduced Charge-Transfer Polymerization

ABSTRACT: The synthesis of a diblock copolymer of styrene and vinyl acetate (VAC), PS-b-PVAC, was performed by successive photoinduced charge-transfer polymerization (CTP) under UV irradiation. A novel amphiphilic diblock copolymer of PS-b-PVA then was obtained by the hydrolysis of the diblock copolymer PS-b-PVAC with sodium ethoxide as a catalyst. Both of them were characterized by Fourier transform infrared, 1 H NMR, and gel permeation chromatography in detail. The effect of the solvents on the CTP and the kinetics of the CTP are discussed

Synthesis of (ABCB)n type ternary amphiphilic multiblock copolymer via poly(ethylene oxide) macro-chain transfer agent

A novel (ABCB)n type ternary amphiphilic multiblock copolymer was synthesized by stepwise insertion of monomers into the trithiocarbonate-embedded poly(ethylene oxide) (PEO) macro-chain transfer agent (PEO-CTA)n. (PEO-CTA)n was synthesized first by coupling of α,ω-dihydroxyl PEO with dicarboxylic trithiocarbonate, then styrene (St) and t-butyl acrylate (tBA) were inserted into the (PEO-CTA)n successively to yield (PEO-b-PS)n and (PEO-b-PS-b-PtBA-b-PS)n, respectively. After hydrolysis of the (PEO-b-PS-b-PtBA-b-PS)n, the final product (PEO-b-PS-b-PAA-b-PS)n was obtained

Synthesis of poly(Ethylene glycol) with sulfadiazine and chlorambucil end groups and investigation of its antitumor activity

alpha-Amino-omega-hydroxyl-poly(ethylene glycol) (PEG) with different molecular weight (M-r = 2100 4400, 7200) were synthesized and used as carrier for the combination of sulfadiazine and chlorambucil. In vivo, all these polymer drugs with sulfadiazine and chlorambucil at each end are water soluble and showed the higher antitumor activity against Lewis lung cancer than the same polymers but without the sulfadiazine. The best one is the sample with molecular weight of 2100. In vitro, however, for the samples with same molecular weights, the polymer drugs with and without sulfadiazine showed the similar results against C6 human breast cancer cells. No obvious difference was found. (C) 2003 Elsevier Ltd. All rights reserved