Increase of thermal stability of tannin acyl hydrolase by covalent immobilization through its carbohydrate side chain : application in tea cream solubilisation

Thermally stimulated current (TSC) measurement was employed to study the thermal stability of electro-optic (EO) polymers, i.e., guest/host polymer DR1/PMMA and side-chain polymer PMMA-co-DR1. Here the isothermal relaxation test showed that the relaxation time τ (85 °C) of side-chain polymer PMMA-co-DR1 is longer than that of guest/host polymer DR1/PMMA. TSC peaks appeared symmetrically in proportion to the poling electric field Ep, indicating that DR1 molecules make a dominant contribution to dipolar depolarization. Thermal sampling (TS) method showed that the activation energy of the DR1/PMMA is around 1 eV, while that of the PMMA-co-DR1 is distributed > 1 eV. Results suggested that side-chain polymer is preferable to the guest/host polymer in the thermal stability. TSC measurement is helpful as a conventional method for studying the life time of EO polymers in terms of dipolar motion.

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Chemical modification of schizophyllan by introduction of a cationic charge into the side chain which enhances the thermal stability of schizophyllan–poly(C) complexes

Chemical Communications ◽

10.1039/b105609n ◽

2001 ◽

pp. 1962-1963 ◽

Cited By ~ 16

Author(s):

Kazuya Koumoto ◽

Taro Kimura ◽

Masami Mizu ◽

Kazuo Sakurai ◽

Seiji Shinkai

Keyword(s):

Thermal Stability ◽

Chemical Modification ◽

Side Chain ◽

Thermal Stability Of

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Enhancing thermal stability of nonfullerene organic solar cells via fluoro-side-chain engineering

Journal of Materials Chemistry C ◽

10.1039/c9tc02700a ◽

2019 ◽

Vol 7 (31) ◽

pp. 9513-9522 ◽

Cited By ~ 7

Author(s):

Yue Xin ◽

Guang Zeng ◽

JinYang OuYang ◽

Xiaoli Zhao ◽

Xiaoniu Yang

Keyword(s):

Thermal Stability ◽

Solar Cells ◽

Organic Solar Cells ◽

Side Chain ◽

Thermal Stability Of

Two novel side-chain fluorinated n-SMAs were synthesized to study the effect of fluoro-side-chain engineering on the thermal stability of OSCs.

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The thermal degradation of some polymeric di-alkyl esters of itaconic acid

Journal of the Serbian Chemical Society ◽

10.2298/jsc131214154p ◽

2013 ◽

Vol 78 (12) ◽

pp. 2179-2200 ◽

Cited By ~ 3

Author(s):

Ivanka Popovic ◽

Lynne Katsikas

Keyword(s):

Thermal Stability ◽

Thermal Degradation ◽

Itaconic Acid ◽

Degradation Mechanism ◽

General Structure ◽

Chain Scission ◽

Side Chain ◽

Biotechnological Production ◽

Methacrylate Monomers ◽

Thermal Stability Of

One group of polymers that may help relieve the dependence on crude oil is based on itaconic acid, the biotechnological production of which has become feasible. Itaconic acid and its derivatives can easily be incorporated into polymers and may serve as a substitute for petrochemically derived acrylate or methacrylate monomers. The applications of polymers based on itaconic di-esters depend largely on their thermal stability. The thermal stability of poly(di-itaconates) is dependent, not only on the general structure of the monomer repeating unit, but also on the structure of the ester substituent. Depolymerization, initiated by b-scission or random main chain scission, is the dominant thermolysis mechanism in most cases. The depolymerization of poly-(di-itaconates) may be accompanied by de-esterification, elimination, cross-linking, random main or side chain scission and carbonization. Comparison of the thermal degradation mechanism of polymeric di-esters of itaconic acid to that of corresponding poly(methacrylates) confirms the viability of substituting poly(methacrylates) by poly(di-itaconates).

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Physico-Chemical and Light-Induced Properties of Quinoline Azo-dyes Polymers

International Journal of Molecular Sciences ◽

10.3390/ijms21165755 ◽

2020 ◽

Vol 21 (16) ◽

pp. 5755

Author(s):

Dariusz Chomicki ◽

Oksana Kharchenko ◽

Lukasz Skowronski ◽

Jolanta Kowalonek ◽

Anna Kozanecka-Szmigiel ◽

...

Keyword(s):

Thin Films ◽

Thermal Stability ◽

Optical Properties ◽

Azo Dyes ◽

Side Chain ◽

Photochromic Properties ◽

Scanning Calorimetry ◽

Dsc Measurements ◽

Physico Chemical ◽

Thermal Stability Of

We present investigation of optical and photochromic properties as well as of surface quality of thin films of novel methacrylic polymers with 8-hydroxyquinoline azo-dyes in side-chain. Additionally, thermal stability of polymer powders was examined and their glass transition temperature was determined. Optical properties (extinction coefficient and refractive index) were determined by spectroscopic ellipsometry (SE) combined with absorbance measurements. Photoresponsive behavior was investigated by determination of photoisomerization rates under irradiation with unpolarized 365 nm light, as well as by conduction of holographic grating inscription experiment. Thin film quality was determined by atomic force microscopy (AFM) measurements. Thermal analysis was performed by thermogravimetric (TG), derivative thermogravimetric (DTG) and differential scanning calorimetry (DSC) measurements. We found that optical properties as well as photoisomerization rates of investigated polymers are dependent on the substituent in the para position of the phenyl ring. Surface relief grating inscription was successfully generated only for materials with chromophores containing dimethylamino (N(CH3)2) and methyl (CH3) substituents, but all materials exhibited birefringence grating in the bulk. Surface of most thin films was very smooth, but its quality was impaired by neutral (H) as well as carboxyl (COOH) substituent. Thermal stability of copolymers with side-chain chromophores was improved compared to pure poly(methyl methacrylate) (PMMA).

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