scholarly journals Cationic disulfide-functionalized worm gels

2017 ◽  
Vol 8 (38) ◽  
pp. 5962-5971 ◽  
Author(s):  
L. P. D. Ratcliffe ◽  
K. J. Bentley ◽  
R. Wehr ◽  
N. J. Warren ◽  
B. R. Saunders ◽  
...  

Two types of cationic disulfide diblock copolymer worm gels are prepared by reacting cystamine with epoxy groups located within the steric stabilizer chains.

2020 ◽  
Vol 11 (39) ◽  
pp. 6343-6355
Author(s):  
Fiona L. Hatton ◽  
Matthew J. Derry ◽  
Steven P. Armes

The rational synthesis of epoxy-functional diblock copolymer nano-objects has been achieved by RAFT aqueous emulsion polymerisation of glycidyl methacrylate under mild conditions (50 °C, pH 7) to preserve the epoxy groups.


1994 ◽  
Vol 4 (12) ◽  
pp. 2231-2248 ◽  
Author(s):  
Mohan Sikka ◽  
Navjot Singh ◽  
Frank S. Bates ◽  
Alamgir Karim ◽  
Sushil Satija ◽  
...  

2017 ◽  
Vol 54 (2) ◽  
pp. 341-344
Author(s):  
Anda Ionelia Mihai (Voicu) ◽  
Sorina Alexandra Garea ◽  
Eugeniu Vasile ◽  
Cristina Lavinia Nistor ◽  
Horia Iovu

The goal of this paper was to study the modification of porous clay heterostructures (PCHs) with various silane coupling agents. Two commercial coupling agents (3-aminopropyl-triethoxysilane (APTES) and 3-glycidoxypropyl-trimethoxysilane (GPTMS)) with different functional groups (amine and epoxy groups) were used as modifying agents for the PCHs functionalization. The functionalization of PCH with APTES and GPTMS was evaluated by Fourier transform infrared (FTIR) spectrometry, thermogravimetric analysis (TGA), X-Ray Diffractions (XRD) and BET Analysis. FTIR spectra of modified PCHs confirmed the presence of characteristic peaks of silane coupling agents. TGA results highlighted an increase of weight loss for the modified PCHs that was assigned to the degradation of silane coupling agents (APTES and GPTMS) attached to the PCHs. The XRD results showed that the structure of modified PCHs was influenced by the type of the silane coupling agent. The functionalization of PCHs with silane coupling agents was also confirmed by BET analysis. Textural parameters (specific surface area (SBET), total pore volume (Vt )) suggested that the modified PCHs exhibit lower values of SBET and a significant decrease of total pore volume than unmodified PCHs.


2021 ◽  
Vol 13 (2) ◽  
pp. 3278-3286
Author(s):  
Juan Zhang ◽  
Andrew N. Keith ◽  
Sergei S. Sheiko ◽  
Xuehui Wang ◽  
Zhigang Wang

2021 ◽  
Author(s):  
Saul J. Hunter ◽  
Joseph R. Lovett ◽  
Oleksandr O. Mykhaylyk ◽  
Elizabeth R. Jones ◽  
Steven P. Armes

RAFT aqueous emulsion polymerization of hydroxybutyl methacrylate using a poly(glycerol monomethacrylate) precursor leads to diblock copolymer spheres, worms or vesicles. A pseudo-phase diagram is constructed and the vesicles are briefly evaluated as a Pickering emulsifier.


e-Polymers ◽  
2021 ◽  
Vol 21 (1) ◽  
pp. 491-499
Author(s):  
Fukai Yang ◽  
Hao Yu ◽  
Yuyuan Deng ◽  
Xinyu Xu

Abstract In this article, five kinds of soybean oil-based polyols (polyol-E, polyol-P, polyol-I, polyol-B, and polyol-M) were prepared by ring-opening the epoxy groups in epoxidized soybean oil (ESO) with ethyl alcohol, 1-pentanol, isoamyl alcohol, p-tert-butylphenol, and 4-methoxyphenol in the presence of tetrafluoroboric acid as the catalyst. The SOPs were characterized by FTIR, 1H NMR, GPC, viscosity, and hydroxyl numbers. Compared with ESO, the retention time of SOPs is shortened, indicating that the molecular weight of SOPs is increased. The structure of different monomers can significantly affect the hydroxyl numbers of SOPs. Due to the large steric hindrance of isoamyl alcohol, p-hydroxyanisole, and p-tert-butylphenol, SOPs prepared by these three monomers often undergo further dehydration to ether reactions, which consumes the hydroxyl of polyols, thus forming dimers and multimers; therefore, the hydroxyl numbers are much lower than polyol-E and polyol-P. The viscosity of polyol-E and polyol-P is much lower than that of polyol-I, polyol-B, and polyol-M. A longer distance between the molecules and the smaller intermolecular force makes the SOPs dehydrate to ether again. This generates dimer or polymers and makes the viscosity of these SOPs larger, and the molecular weight greatly increases.


Sign in / Sign up

Export Citation Format

Share Document