Synthesis and Characterization of Polystyrene/Mesoporous Diatomite Composites via Activators Generated by Electron Transfer for Atom Transfer Radical Polymerization

Davoudizadeh, Soroush; Sarsabili, Mohammadreza; Khezri, Khezrollah

doi:10.1515/zpch-2016-0812

Cited by 15 publications

(11 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…High thermal stability of diatomite platelets and also physical interaction between surface of the diatomite platelets and poly (styrene‐co‐methyl methacrylate) chains are the main reasons for enhancing thermal stability of the prepared nanocomposites. It is clear that, by increasing diatomite platelets content, more improvements in thermal stability can be obtained . Additionally, hindrance effect of the diatomite platelets on the poly (styrene‐co‐methyl methacrylate) chains movement and restriction of oxygen permeation by these sheets are the other reasons for higher thermal stability of the nanocomposites.…”

Section: Resultssupporting

confidence: 89%

“…It is clear that, by increasing diatomite platelets content, more improvements in thermal stability can be obtained. 39,40 Additionally, hindrance effect of the diatomite platelets on the poly (styrene-co-methyl methacrylate) chains movement and restriction of oxygen permeation by these sheets are the other reasons for higher thermal stability of the nanocomposites.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Reverse atom transfer radical random copolymerization of styrene and methyl methacrylate in the presence of diatomite nanoplatelets

Sarsabili

Rahmatolahzadeh

Shobeiri

et al. 2017

Polymers for Advanced Techs

Self Cite

View full text Add to dashboard Cite

Diatomite nanoplatelets were used for in situ random copolymerization of styrene and methyl methacrylate by reverse atom transfer radical polymerization to synthesize different well-defined nanocomposites. Inherent features of the pristine diatomite nanoplatelets were evaluated by Fourier transform infrared spectroscopy, nitrogen adsorption/desorption isotherm, scanning electron microscope, and transmission electron microscope. Gas and size exclusion chromatography was also used to determine conversion and molecular weight determinations, respectively.Considerable increment in conversion (from 81% to 97%) was achieved by adding 3 wt% diatomite nanoplatelets in the copolymer matrix. Moreover, molecular weight of random copolymer chains was increased from 12 890 to 13 960 g·mol −1 by addition of 3 wt% diatomite nanoplatelets; however, polydispersity index (PDI) values increases from 1.36 to 1.59. Proton nuclear magnetic resonance spectroscopy was used to evaluate copolymers composition. Thermal gravimetric analysis results indicate that thermal stability of the nanocomposites is improved by adding diatomite nanoplatelets. Differential scanning calorimetry shows an increase in glass transition temperature from 66°C to 71°C by adding 3 wt% of diatomite nanoplatelets. 8-10Diatoms are tiny single-celled plants that live inside a hard shell.Diatoms can be found in large quantities in both salt and sweet water.When the plants inside the shell die, the shell sinks to the bottom of lakes and, by accumulation of them over centuries, finally, the material called diatomaceous earth or the more lightweight rock called diatomite will be formed.

show abstract

Section: Resultssupporting

confidence: 89%

Section: Resultsmentioning

confidence: 99%

Reverse atom transfer radical random copolymerization of styrene and methyl methacrylate in the presence of diatomite nanoplatelets

Sarsabili

Rahmatolahzadeh

Shobeiri

et al. 2017

Polymers for Advanced Techs

Self Cite

View full text Add to dashboard Cite

show abstract

“…This negative effect of the H-SAN on the molecular weight of the copolymer chains can be also attributed to the three above mentioned reasons (impurity role, restric- tion of the mobility, and irreversible reactions). [33][34][35] By precise evaluation of the results an appropriate agreement between experimental and theoretical Mn values are observed that this agreement can be considered as a suitable evidence for demonstration of the living nature of the copolymerization system.…”

Section: Resultsmentioning

confidence: 58%

“…Negative effect of the modified silica aerogel nanoparticles on the copolymerization may be attributed to the three main factors; i) Impurity role of the H-SAN: it is demonstrated that existence of some nano-fillers in the copolymerization media can disturb the ATRP equilibrium and therefore products with lower conversion, lower molecular weights, and higher PDI values can be prepared. [33][34][35] ii) Restriction of the mobility: due to the porous structure of the H-SAN, mobility of the radicals and growing macro-radicals in the solution can be restricted and therefore copolymerization rate and monomers conversion can be decreased. It is clear that by increasing modified silica aerogel nanoparticles content, more restriction will be happened and therefore higher decrement in the conversion can be obtained.…”

Section: Resultsmentioning

confidence: 99%

“…Thus, growing radicals can irreversibly react with the moieties (such as un-modified hydroxyl groups) on the H-SAN and therefore can present negative effect on the copolymerization rate and conversion. [33][34][35] Variation of number-averaged molecular weight (Mn) with conversion during the copolymerization is represented in figure 6. Theoretical line in this figure is displayed to present theoretical Mn values for the various conversions.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

A Study on the Properties of Poly (Styrene-co-Methyl Methacrylate)/Silica Aerogel Nanocomposites Prepared via in situ SR&NI ATRP

Khezri

Fazli

2018

ACSi

Self Cite

View full text Add to dashboard Cite

Simultaneous reverse and normal initiation technique for atom transfer radical copolymerization (SR&NI ATRP) of styrene and methyl methacrylate in the presence of hexamethyldisilazane (HMDS)-modified silica aerogel nanoparticles (H-SAN) and investigating the effect of addition of H-SAN on the copolymerization and thermal properties of the products are discussed. Some unique features of the H-SAN are evaluated using nitrogen adsorption/desorption isotherm, SEM and TEM. Conversion and molecular weight determinations were carried out using GC and SEC respectively. Adding of H-SAN by 3 wt% results in decrement of conversion from 94 to 73%. In addition, molecular weight of copolymer chains decreases from 19500 to 16000 g.mol-1. However, polydispersity index values increases from 1.29 to 1.65. Linear increase of ln(M 0 /M) with time for all the samples shows that copolymerization proceeds in a living manner. Increasing thermal stability of the nanocomposites is demonstrated by TGA. DSC results show a decrease in glass transition temperature from 70.3 to 63.5 °C by addition of 3 wt% H-SAN.

show abstract

Kinetics and thermal studies for the copolymerization of styrene and methyl methacrylate by incorporation of mesoporous diatomite

Khezri

Fazli

2020

Materialwissenschaft Werkst

View full text Add to dashboard Cite

Activators generated by electron transfer (AGET) for atom transfer radical copolymerization (ATRP) was employed to synthesize tailor‐made random poly (styrene‐co‐methyl methacrylate)/mesoporous kieselgur nanocomposites. Some inherent features of the mesoporous kieselgur platelets were studied by nitrogen adsorption/desorption isotherm and transmission electron microscopy images. Conversion and molecular weight determinations were carried out using gas chromatography and size exclusion chromatography respectively. Addition of 3 wt.% mesoporous kieselgur platelets results in increments of conversion from 72 % to 87 % and molecular weight of copolymer chains from 15986 g mol−1 to 18564 g mol−1 respectively; however, polydispersity index values increases from 1.19 to 1.48. Increasing thermal stability of the nanocomposites is demonstrated by thermogravimetric analysis. Differential scanning calorimetry shows an increase in glass transition temperature from 70.6 °C to 75.7 °C by adding 3 wt.% of mesoporous kieselgur platelets.

show abstract

Synthesis and Characterization of Polystyrene/Mesoporous Diatomite Composites via Activators Generated by Electron Transfer for Atom Transfer Radical Polymerization

Abstract: Diatomite platelets were employed to synthesize different polystyrene/diatomite composites. Mesoporous diatomite platelets were used for

Cited by 15 publications

References 42 publications

Reverse atom transfer radical random copolymerization of styrene and methyl methacrylate in the presence of diatomite nanoplatelets

Reverse atom transfer radical random copolymerization of styrene and methyl methacrylate in the presence of diatomite nanoplatelets

A Study on the Properties of Poly (Styrene-co-Methyl Methacrylate)/Silica Aerogel Nanocomposites Prepared via in situ SR&NI ATRP

Kinetics and thermal studies for the copolymerization of styrene and methyl methacrylate by incorporation of mesoporous diatomite

Contact Info

Product

Resources

About