Catalyzed chain growth polymerisation of ethylene using lanthanidocenes/dialkylmagnesium: further developments and one pot synthesis of narrow dispersed high molecular weight fatty alcohols

2020 ◽  
Vol 10 (20) ◽  
pp. 6809-6824
Author(s):  
T. Chenal ◽  
M. Drelon ◽  
B. Marsh ◽  
F. F. Silva ◽  
M. Visseaux ◽  
...  

Ethylene polymerisation was performed via an improved in situ Ln/Mg CCG process and applied to the synthesis of high Mn linear alcohols.

1998 ◽  
Vol 10 (1) ◽  
pp. 51-59
Author(s):  
Amane Mochizuki ◽  
Masahiro Yoshioka ◽  
Michie Sakamoto ◽  
Takahiro Fukuoka ◽  
Mitsuru Ueda

A one-pot synthesis of aromatic polycarbodiimide from aromatic diamine has been developed. This method involves the preparation of carbamate by the reaction of 4, 4′-hexafluoroisopropylidenebis( p-phenyleneoxy)dianiline (6FPA) with phenylchloroformate, followed by the transformation of the carbamate with trimethylsilylchloride-triethylamine to diisocyanate, and then the polycondensation of the resulting diisocyanate in the presence of 3-methyl-1-phenyl-2-phosopholene-1-oxide. The polycarbodiimide (6FPCD) from 6FPA was obtained in quantitative yield having a number average molecular weight up to 5000. The thermal treatment of 6FPCD gave a crosslinkined polymer having a high glass transition temperature up to 200 °C.


2014 ◽  
Vol 79 (20) ◽  
pp. 9594-9602 ◽  
Author(s):  
David Hvasanov ◽  
Ekaterina V. Nam ◽  
Joshua R. Peterson ◽  
Dithepon Pornsaksit ◽  
Jörg Wiedenmann ◽  
...  

RSC Advances ◽  
2015 ◽  
Vol 5 (106) ◽  
pp. 87311-87319 ◽  
Author(s):  
Ziqing Wang ◽  
Xiangui Yang ◽  
Shaoying Liu ◽  
Jing Hu ◽  
Hua Zhang ◽  
...  

Aliphatic polycarbonates with Mw greater than 100 000 g mol−1 with satisfactory yield can be synthesized by one-pot melt transesterification of diphenyl carbonate with aliphatic diols at equimolar amounts using Zn(OAc)2 as a catalyst.


2015 ◽  
Vol 6 (37) ◽  
pp. 6739-6745 ◽  
Author(s):  
Xiaofeng Wang ◽  
Robert W. Graff ◽  
Yi Shi ◽  
Haifeng Gao

A one-pot synthesis was reported to produce hyperstar polymers with high molecular weight, low polydispersity and no detectable star coupling reactions.


2020 ◽  
Vol 24 (8) ◽  
pp. 900-908
Author(s):  
Ram Naresh Yadav ◽  
Amrendra K Singh ◽  
Bimal Banik

Numerous O (oxa)- and S (thia)-glycosyl esters and their analogous glycosyl acids have been accomplished through stereoselective glycosylation of various peracetylated bromo sugar with benzyl glycolate using InBr3 as a glycosyl promotor followed by in situ hydrogenolysis of resulting glycosyl ester. A tandem glycosylating and hydrogenolytic activity of InBr3 has been successfully investigated in a one-pot procedure. The resulting synthetically valuable and virtually unexplored class of β-CMGL (glycosyl acids) could serve as an excellent potential chiral auxiliary in the asymmetric synthesis of a wide range of enantiomerically pure medicinally prevalent β-lactams and other bioactive molecules of diverse medicinal interest.


Coatings ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 584
Author(s):  
Rui Dang ◽  
Liqiu Ma ◽  
Shengguo Zhou ◽  
Deng Pan ◽  
Bin Xia

Ultra-high molecular weight polythene (UHMWPE), with outstanding characteristics, is widely applied in modern industry, while it is also severely limited by its inherent shortcomings, which include low hardness, poor wear resistance, and easy wear. Implementation of feasible protection on ultra-high molecular weight polythene to overcome its shortcomings would be of significance. In the present study, amorphous carbon (a-C) film was fabricated on ultra-high molecular weight polythene (UHMWPE) to provide good protection, and the relevant growth mechanism of a-C film was revealed by controlling carbon plasma currents. The results showed the in situ transition layer, in the form of chemical bonds, was formed between the UHMWPE substrate and the a-C film with the introduction of carbon plasma, which provided strong adhesion, and then the a-C film continued epitaxial growth on the in situ transition layer with the treatment of carbon plasma. This in situ growth of a-C film, including the in situ transition layer and the epitaxial growth layer, significantly improved the wetting properties, mechanical properties, and tribological properties of UHMWPE. In particular, good protection by in situ growth a-C film on UHMWPE was achieved during sliding wear.


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