Dimethyl sulfoxide as a green solvent for successful precipitative polyheterocyclization based on nucleophilic aromatic substitution, resulting in high molecular weight PIM-1

2016 ◽  
Vol 26 (4) ◽  
pp. 362-364 ◽  
Author(s):  
Igor I. Ponomarev ◽  
Inesa V. Blagodatskikh ◽  
Alexander V. Muranov ◽  
Yulia A. Volkova ◽  
Dmitrii Yu. Razorenov ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Dimethyl Sulfoxide ◽  
High Molecular Weight ◽  
Nucleophilic Aromatic Substitution ◽  
Aromatic Substitution ◽  
Green Solvent

Synthesis of Segmented Anisotropic-Isotropic Poly(Aryl Ester)Poly(Arylene Ether) Copolymers

1989 ◽  
Vol 175 ◽  
Author(s):  
J. E. McGratn ◽  
K. L. Cooper ◽  
W. Waehamad ◽  
H. Huang ◽  
G. L. Wilkes
Keyword(s):  
Molecular Weight ◽  
Liquid Crystal ◽  
Benzoic Acid ◽  
Liquid Crystalline ◽  
Average Molecular Weight ◽  
Nucleophilic Aromatic Substitution ◽  
Copolymer Composition ◽  
Aromatic Substitution ◽  
Scanning Calorimetry ◽  
Arylene Ether

AbstractCarboxyl functional poly(arylene ether) oligomers of controlled number average molecular weight were synthesized via nucleophilic aromatic substitution step polymerization using p-hydroxy benzoic acid as the molecular weight and end group controlling reagents. The subsequent functionalized polyarylene ethers were copolymerized with acetoxy benzoic acid or acetoxyphenoxy benzoic acid via melt acidolysis procedures. Successful copolymers were generated using chlorobenzene as a solvent for the first s age of the reaction followed by melt reaction at temperatures as high as 325°C. Resulting copolymer composition and segment size were investigated. It was possible to prepare improved solvent resistant copolymers through incorporation of the liquid crystal polyester (LCP) segment. Extraction tests using boiling chloroform showed that a high percentage of segmented copolymer were generated. Swelling characteristics were also noted and were observed to decrease as a function of the LCP concentration utilized. Multiple transitions were observed in differential scanning calorimetry consistent with Tg's, Tm's and possibly with liquid crystal transitions. Optical microscopy showed an ordered microstructure developed which is consistent with the presence of liquid crystalline phases. The materials were successfully compression molded to afford tough coherent films at all compositions, implying the likelihood of improved compressive strength relative to the LCP homo- or copolyesters.

A metal-free method for ultra-high molecular weight polyacrylonitrile under dimethyl sulfoxide

Polymer ◽  
2020 ◽  
pp. 123245
Author(s):  
Guanchun Rui ◽  
Qiang Lv ◽  
Jianmin Lu ◽  
Tianyu Wu ◽  
Shuai Zhao ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Dimethyl Sulfoxide ◽  
High Molecular Weight ◽  
Metal Free ◽  
Ultra High Molecular Weight

Dextran Based Polyampholyte Having Cryoprotective Properties

2013 ◽  
Vol 1498 ◽  
pp. 33-38
Author(s):  
Minkle Jain ◽  
Kazuaki Matsumura
Keyword(s):  
Tissue Engineering ◽  
Molecular Weight ◽  
Dimethyl Sulfoxide ◽  
High Molecular Weight ◽  
Carboxyl Groups ◽  
Engineering Applications ◽  
L929 Cells ◽  
Cryoprotective Agent

ABSTRACTDimethyl sulfoxide (DMSO) has been used for several decades as the most efficient cryoprotective agent (CPA) for many types of cells in spite of its cytotoxicity and its effect on differentiation. Recently we showed that carboxylated poly-L-lysine, which is classified as a polyampholyte, has a cryoprotective effect on cells in solution without any other cryoprotectant. Here we developed high molecular weight polyampholytes with an appropriate ratio of amino and carboxyl groups and evaluated their cryopreservation efficiency. A novel polyampholyte based on naturally available polymer dextran, in which we introduced both amino and carboxyl groups shows an excellent post thaw-survival efficiency of more than 90% of murine L929 cells. It can serve as the sole high molecular weight CPA for tissue engineering applications without animal derived materials.

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