On the influence of the chemical structure of polymers on their thermal stability

Designing novel low-melting, high-rigidity phthalonitrile resin is of great significance in the current context of development. In this study, rigid spirocycle acetal structure was introduced into phthalonitrile to reduce the melting point and maintain their thermal stability. The chemical structure of resins was confirmed by nuclear magnetic resonance (NMR) spectrometry, matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) mass spectrometry and Fourier-transform infrared (FTIR) spectroscopy. The curing behaviors were studied by differential scanning calorimetry (DSC). Thermal stability and mechanical properties of the cured resins were investigated by dynamic mechanical thermal analysis (DMTA) and thermogravimetric analysis (TGA). The processability was studied by rheological analysis. The results indicated the three monomers had a low melting temperature, wide processing windows and low viscosities. These polymers did not exhibit Tg from room temperature to 400°C, exhibited superb dynamic mechanical property and thermal stability.

Download Full-text

Thermal Stability as a Function of Chemical Structure.

Journal of Chemical & Engineering Data ◽

10.1021/je60009a020 ◽

1961 ◽

Vol 6 (1) ◽

pp. 87-98 ◽

Cited By ~ 80

Author(s):

E.S. Blake ◽

W.C. Hammann ◽

James W. Edwards ◽

T.E. Reichard ◽

M. R. Ort

Keyword(s):

Thermal Stability ◽

Chemical Structure

Download Full-text

Synthesis of biomass based plasticizer from linoleic acid and cardanol for preparing durable PVC material

10.21203/rs.3.rs-381777/v1 ◽

2021 ◽

Author(s):

Hongying Chu ◽

Huabei Li ◽

Xiaoyan Sun ◽

Yaowang Zhang

Keyword(s):

Thermal Stability ◽

Linoleic Acid ◽

Chemical Structure ◽

Dioctyl Phthalate ◽

H Nmr ◽

Plasticized Pvc ◽

Migration Resistance ◽

Ft Ir ◽

And Migration ◽

Thermal Stability Of

Abstract In this paper, we synthesized a kind of bio-based plasticizer epoxidized linoleic acid cardanol ester(ELCE) from cardanol and linoleic acid. Its chemical structure was characterized with FT-IR and 1H NMR. Polyvinyl chloride(PVC) blends plasticized with ELCE were prepared via thermoplastic blending with torque rheometer. The performance including torque, mechanical property, thermal stability, plasticizing property and migration resistance of plasticized PVC blends were investigated and compared with plasticized PVC blends with commercial plasticizer dioctyl phthalate(DOP). The results showed that ELCE improved thermal stability of PVC blends. ELCE played more excellent plasticizing effect on PVC blends than DOP. The better solvent extraction resistance and volatile resistance of ELCE make it impossible to completely replace DOP in PVC products.

Download Full-text

Oxidative Polymerization of 3-Amino,2'-,(3')–Nitrodiphenylazomethin

Materials Science Forum ◽

10.4028/www.scientific.net/msf.935.134 ◽

2018 ◽

Vol 935 ◽

pp. 134-139 ◽

Cited By ~ 1

Author(s):

Timur A. Borukaev ◽

A.Kh. Malamatov ◽

M.K. Vindizheva ◽

A.V. Orlov ◽

S.G. Kiseleva

Keyword(s):

Thermal Stability ◽

Thermal Properties ◽

Chemical Structure ◽

Oxidative Polymerization ◽

Polymerization Process ◽

Chain Growth ◽

Polymer Product ◽

Two Stages

Oxidative polymerization of 3-amino,2'-,(3')-nitrodiphenylazomethine was carried out in various ways. A possible mechanism for the polymerization of 3-amino,2'-,(3')- nitrodiphenylazomethine, where chain growth occurs as type N-C, is shown. It has been found that the yield of the polymer product is affected by the polymerization process and time. The chemical structure of the polymers obtained is established. The study of the thermal properties of polymers showed a low thermal stability and the process of destruction proceeds in two stages.

Download Full-text

3D Printed Chromophoric Sensors

Chemosensors ◽

10.3390/chemosensors9110317 ◽

2021 ◽

Vol 9 (11) ◽

pp. 317

Author(s):

Zachary Brounstein ◽

Jarrod Ronquillo ◽

Andrea Labouriau

Keyword(s):

Thermal Stability ◽

3D Printing ◽

Material Properties ◽

Chemical Structure ◽

Elevated Temperatures ◽

Advanced Manufacturing ◽

Color Changes ◽

Printed Sensors ◽

3D Printed ◽

Manufacturing Techniques

Eight chromophoric indicators are incorporated into Sylgard 184 to develop sensors that are fabricated either by traditional methods such as casting or by more advanced manufacturing techniques such as 3D printing. The sensors exhibit specific color changes when exposed to acidic species, basic species, or elevated temperatures. Additionally, material properties are investigated to assess the chemical structure, Shore A Hardness, and thermal stability. Comparisons between the casted and 3D printed sensors show that the sensing devices fabricated with the advanced manufacturing technique are more efficient because the color changes are more easily detected.

Download Full-text

Systematic Characterization of Different Quaternary Ammonium Salts to be Used in Organoclays

Materials Science Forum ◽

10.4028/www.scientific.net/msf.727-728.1552 ◽

2012 ◽

Vol 727-728 ◽

pp. 1552-1556

Author(s):

Renata Barbosa ◽

Dayanne Diniz Souza ◽

Edcleide Maria Araújo ◽

Tomás Jefférson Alves de Mélo

Keyword(s):

Thermal Stability ◽

Quaternary Ammonium ◽

Chemical Structure ◽

Quaternary Ammonium Salts ◽

Ammonium Salts ◽

Degradation Mechanisms ◽

Scanning Calorimetry ◽

Higher Temperature ◽

Thermal Stability Of

Studies of degradation have verified that the decomposition of some quaternary ammonium salts can begin to be significant at the temperature of about 180 ° C and like most thermoplastics are processed at least around this temperature, the thermal stability of the salt in clay should always be considered. Some salts are more stable than others, being necessary to study the degradation mechanisms of each case. In this work, four quaternary ammonium salts were characterized by differential scanning calorimetry (DSC) and thermogravimetry (TG). The results of DSC and TG showed that the salts based chloride (Cl-) anion begin to degrade at similar temperatures, while the salt based bromide (Br-) anion degrades at higher temperature. Subsequently, a quaternary ammonium salt was chosen to be used in organoclays, depending on its chemical structure and its thermal behavior.

Download Full-text

Efficient Synthesis of PVDF/PI Side-by-Side Bicomponent Nanofiber Membrane with Enhanced Mechanical Strength and Good Thermal Stability

Nanomaterials ◽

10.3390/nano9010039 ◽

2018 ◽

Vol 9 (1) ◽

pp. 39 ◽

Cited By ~ 16

Author(s):

Ming Cai ◽

Hongwei He ◽

Xiao Zhang ◽

Xu Yan ◽

Jianxin Li ◽

...

Keyword(s):

Heat Treatment ◽

Thermal Stability ◽

Mechanical Strength ◽

Polyvinylidene Fluoride ◽

Chemical Structure ◽

Electrospun Fiber ◽

Nanofiber Membrane ◽

Application Range ◽

Good Thermal Stability ◽

Filtration Properties

Bicomponent composite fibers, due to their unique versatility, have attracted great attention in many fields, such as filtration, energy, and bioengineering. Herein, we efficiently fabricated polyvinylidene fluoride/polyimide (PVDF/PI) side-by-side bicomponent nanofibers based on electrospinning, which resulted in the synergism between PVDF and PI, and eventually obtained the effect of 1 + 1 > 2. Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) were used to characterize the morphology and chemical structure of nanofibers, indicating that a large number of side-by-side nanofibers were successfully prepared. Further, the thermal stability, mechanical strength, and filtration properties of PVDF/PI were carefully investigated. The results revealed that the bicomponent nanofibers possessed both good mechanical strength and remarkable thermal stability. Moreover, the mechanical properties of PVDF/ PI were strengthened by more than twice after the heat treatment (7.28 MPa at 25 °C, 15.49 MPa at 230 °C). Simultaneously, after the heat treatment at 230 °C for 30 min, the filtration efficiency of PVDF/PI membrane was maintained at about 95.45 ± 1.09%, and the pressure drop was relatively low. Therefore, the prepared PVDF/PI side-by-side bicomponent nanofibers have a favorable prospect of application in the field of medium- and high-temperature filtration, which further expands the application range of electrospun fiber membranes.

Download Full-text

The Effect of Acidity Coefficient on Crystallization Behavior of Blast Furnace Slag Fibers

High Temperature Materials and Processes ◽

10.1515/htmp-2015-0280 ◽

2018 ◽

Vol 37 (1) ◽

pp. 33-37

Author(s):

Tie-Lei Tian ◽

Yu-Zhu Zhang ◽

Hong-wei Xing ◽

Jie Li ◽

Zun-Qian Zhang

Keyword(s):

Thermal Stability ◽

Crystallization Kinetics ◽

Blast Furnace Slag ◽

Chemical Structure ◽

Crystallization Behavior ◽

Three Dimensional ◽

Mineral Wool ◽

Mineral Wool Fiber ◽

Kinetics Of ◽

Furnace Slag

AbstractThe chemical structure of mineral wool fiber was investigated by using Fourier Transform Infrared Spectroscopy (FTIR). Next, the glass transition temperature and the crystallization temperature of the fibers were studied. Finally, the crystallization kinetics of fiber was studied. The results show that the chemical bond structure of fibers gets more random with the increase of acidity coefficient. The crystallization phases of the fibers are mainly melilites, and also a few anorthites and diopsides. The growth mechanism of the crystals is three dimensional. The fibers with acidity coefficient of 1.2 exhibit the best thermal stability and is hard to crystallize as it has the maximum aviation energy of crystallization kinetics.

Download Full-text

Investigating the effect of ligand and cation on the properties of metal fluorinated acetylacetonate based magnetic ionic liquids

New Journal of Chemistry ◽

10.1039/c9nj02595b ◽

2019 ◽

Vol 43 (28) ◽

pp. 11334-11341 ◽

Cited By ~ 3

Author(s):

Muhammad Qamar Farooq ◽

Deepak Chand ◽

Gabriel A. Odugbesi ◽

Marcelino Varona ◽

Yaroslav Mudryk ◽

...

Keyword(s):

Thermal Stability ◽

Magnetic Susceptibility ◽

Ionic Liquids ◽

Chemical Structure ◽

Physiochemical Properties ◽

Magnetic Ionic Liquids

The effect of chemical structure on various physiochemical properties including thermal stability, solvent miscibility, magnetic susceptibility and viscosity is studied for acetylacetone based magnetic ionic liquids.

Download Full-text

Study on the Thermal Stability of Selected Ionic Liquids

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.220-221.218 ◽

2015 ◽

Vol 220-221 ◽

pp. 218-223

Author(s):

Tomasz Jan Kaldonski ◽

Stanislaw Cudzilo

Keyword(s):

Higher Education ◽

Thermal Stability ◽

Ionic Liquids ◽

High Temperature ◽

Thermal Resistance ◽

Chemical Structure ◽

Research Project ◽

High Thermal Resistance ◽

Thermal Stability Of

Some results of tests of the thermal stability (and volatility) of selected ionic liquids pondered as lubricating substances in comparison with typical lubricating, mineral and synthetic oils, are presented in the article. The research was carried out within the framework of PBR/15–249/2007/WAT–OR00002904 Research Project Financed by the Ministry of Science and Higher Education, during 2007–2011 [1]. The obtained results confirmed high thermal resistance of ionic liquids. It makes it possible to use the liquids as high temperature lubricating substances. At the same time, it has been stated that the thermal resistance of ionic liquids depends on the composition and chemical structure of anion and cation.

Download Full-text