Macromolecular structure of coals. IV. Equilibrium swelling studies of coal networks subjected to various treatments

1987 ◽  
Vol 33 (8) ◽  
pp. 2777-2785 ◽  
Author(s):  
Lucy M. Lucht ◽  
N. A. Peppas
Keyword(s):  
Macromolecular Structure ◽  
Equilibrium Swelling ◽  
Swelling Studies

scholarly journals Stimuli Responsive Hydrogels: NIPAM/AAm/Carboxylic Acid Polymers

2019 ◽  
Vol 27 (2) ◽  
pp. 155-184 ◽  
Author(s):  
Yasemin Işikver ◽  
Dursun Saraydin
Keyword(s):  
Thermal Analyses ◽  
The Body ◽  
Polymerization Reaction ◽  
Solution Temperature ◽  
Stimuli Responsive ◽  
Scanning Calorimetry ◽  
Equilibrium Swelling ◽  
Different Temperatures ◽  
Swelling Studies ◽  
Responsive Hydrogels

Abstract Stimuli-responsive hydrogels (SRH) were prepared by using monomers (i.e. N-isopropyl acrylamide; NIPAM and acrylamide; AAm), co-monomers (i.e. methacrylic acid; MPA or mesaconic acid; MFA) and a crosslinker (N, N’-methylene bisacrylamide; N-Bis). SRH have been prepared by thermal free radical polymerization reaction in aqueous solution. Spectroscopic and thermal analyses such as Fourier Transform Infrared Spectroscopy, thermogravimetric analysis and differential scanning calorimetry analysis were performed for SRH characterization. The equilibrium swelling studies by gravimetrically were carried out in different solvents, at the solutions, temperature, pH, and ionic strengths to determine their effect on swelling characteristic of the hydrogels. In addition, cycles equilibrium swelling studies were made with the solutions at different temperatures and at different pH. NIPAM/AAm hydrogel exhibits a lover critical solution temperature (LCST) at 28 oC, whereas NIPAM/AAm-MPA and NIPAM/AAm-MFA hydrogels exhibit a LCST at 31 C and 35 oC, respectively, and the LCST of NIPAM/AAm-MFA hydrogel is close to the body temperature.

Preparation of pH Sensitive Polyacrylic Acid(PAAc) Macroporous Hydrogels in Aqueous NaCl Solutions and their Characterization

2009 ◽  
Vol 79-82 ◽  
pp. 1999-2002
Author(s):  
Yu Hua Xue ◽  
Wen Yuan Zhao ◽  
Shou Feng Sun ◽  
Hu Yu
Keyword(s):  
Polyacrylic Acid ◽  
Response Rates ◽  
Ph Sensitive ◽  
Swelling Ratio ◽  
Ph Changes ◽  
Nacl Concentration ◽  
Equilibrium Swelling ◽  
Swelling Studies ◽  
Equilibrium Swelling Ratio

In this study, macroporous, pH sensitive polyacrylic acid hydrogels were prepared by using different concentration of aqueous NaCl solutions as the polymerization medium. The optical photos showed that the pore morphologies of the hydrogels were dependent on the concentration of NaCl. Swelling studies showed an increase in equilibrium swelling ratio as the NaCl concentration in the polymerization medium increased from 0 to 0.7mol/L. The hydrogels exhibited stronger sensitivity to pH changes, and showed much faster reswelling and deswelling response rates with the NaCl concentration increasing in the polymerization medium.

Equilibrium Swelling Studies of Highly Swollen Acrylamide/Thiosinamine Hydrogels

2009 ◽  
Vol 48 (2) ◽  
pp. 152-157 ◽  
Author(s):  
Ömer Bariş Üzüm ◽  
Semiha Kundakci ◽  
Erdener Karadağ
Keyword(s):  
Equilibrium Swelling ◽  
Swelling Studies

Novel hydrogels from diepoxy-terminated poly(ethylene glycol)s and aliphatic primary diamines: synthesis and equilibrium swelling studies

2009 ◽  
Vol 20 (12) ◽  
pp. 907-915 ◽  
Author(s):  
Mircea Teodorescu ◽  
Bogdan Cursaru ◽  
Paul Stanescu ◽  
Constantin Draghici ◽  
Nicoleta Doriana Stanciu ◽  
...  
Keyword(s):  
Ethylene Glycol ◽  
Poly Ethylene Glycol ◽  
Equilibrium Swelling ◽  
Swelling Studies ◽  
Poly Ethylene
Sign in / Sign up

Export Citation Format

Share Document