Tag: 200-300

Biodegradation Control of Chitosan Materials by Surface Modification with Copolymers of Glycidyl Methacrylate and Alkyl Methacrylates was written by Bryuzgin, Evgeny;Bryuzgina, Ekaterina;Yartseva, Vitaliya;Belina, Kristina;Makevnina, Olga;Kolyaganova, Olga;Klimov, Viktor;Navrotskiy, Alexander;Novakov, Ivan. And the article was included in Fibers and Polymers in 2022.Recommanded Product: 3063-94-3 The following contents are mentioned in the article:

Chitosan is a promising polymer from natural polysaccharides, which is an environmentally friendly compound from renewable raw materials. Chitosan has biodegradability, biocompatibility, and antibacterial and other activities. In this article, we report the biodegradation control of chitosan materials by use of random copolymers based on glycidyl methacrylate and (fluoro)alkyl methacrylates as surface modifiers. We show that grafting of copolymers allows increasing the hydrophobicity of chitosan materials with initial contact angles up to 114° from 89° for films and up to 154° from 123° for aerogels. We demonstrate that modified aerogels retain contact angles of more than 150° for a long contact time with water while the initial aerogel fully wets for 30 s. The resulting chitosan aerogels have high porosity with a pore size of 100-200 μm, and the pore walls are 0.6-0.7-μm-thick film formations. Our study of lyophilic properties of modified chitosan substrates showed a change in the hydrophobicity of the materials as a function of length of the hydrocarbon radical in the side groups of the (fluoro)alkyl methacrylates in the copolymers. We demonstrate that the rate of biodegradation of the resulting materials decreases with an increase in the number of hydrophobic groups in the modifier. The obtained chitosan materials with hydrophobic coatings have potential as a protective layer for wound dressings with an extended service life. This study involved multiple reactions and reactants, such as 1,1,1,3,3,3-Hexafluoroisopropylmethacrylate (cas: 3063-94-3Recommanded Product: 3063-94-3).

1,1,1,3,3,3-Hexafluoroisopropylmethacrylate (cas: 3063-94-3) belongs to esters. Esters perform as high-grade solvents for a broad array of plastics, plasticizers, resins, and lacquers, and are one of the largest classes of synthetic lubricants on the commercial market. Polyesters are important plastics, with monomers linked by ester moieties. Many esters have the potential for conformational isomerism, but they tend to adopt an s-cis (or Z) conformation rather than the s-trans (or E) alternative, due to a combination of hyperconjugation and dipole minimization effects. The preference for the Z conformation is influenced by the nature of the substituents and solvent, if present. Lactones with small rings are restricted to the s-trans (i.e. E) conformation due to their cyclic structure.Recommanded Product: 3063-94-3

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Laboratory evaluation of the sex pheromone and mating inhibitor of the red bollworm Diparopsis castanea Hampson (Lepidoptera, Noctuidae) was written by Marks, R. J.. And the article was included in Bulletin of Entomological Research in 1976.Computed Properties of C14H24O2 The following contents are mentioned in the article:

The four components of the sex pheromone of D. castanea are dodecan-1-yl acetate (I) [112-66-3], trans-9-dodecen-1-yl acetate (II) [35148-19-7], 11-dodecen-1-yl acetate (III) [35153-10-7], and trans-9,11-dodecadien-1-yl acetate (IV) [50767-78-7]. Increasing the proportion of II in a I/II/III/IV mixture progressively decreased male excitation; in the absence of I all concentrations of II tested were equally inhibitory. The synthetic combination of 80% IV (93% trans:7% cis) and 20% III (dicastalure), was 485-fold more potent in eliciting male activity than a female sex pheromone gland extract Reduction in male response to crude extract occurred through exposure of males to glandular II and through reduced pheromone volatility caused by extracted triglycerides. Maximum quantities of pheromone were detected in the female sex pheromone gland 6-12 h into scotophase and for ≥30 min into photophase. Greater bioassay responses were elicited by the optimal field combination of 80% IV and 20% III than for other ratios tested. Excitation and clasper extension were observed in response to the nonattractive III; this indicates a role in close-range mating behavior for this component. The threshold level of male response to sex pheromone occurred at an aerial concentration of 9.2 mols. IV/mm3/s. This suggests that aerial concentrations of 102-103 times the male threshold response level may be sufficient to cause successful communication disruption in the field. This study involved multiple reactions and reactants, such as (E)-Dodeca-9,11-dien-1-yl acetate (cas: 50767-78-7Computed Properties of C14H24O2).

(E)-Dodeca-9,11-dien-1-yl acetate (cas: 50767-78-7) belongs to esters. Esters are also usually derived from carboxylic acids. It may also be obtained by reaction of acid anhydride or acid halides with alcohols or by the reaction of salts of carboxylic acids with alkyl halides. Cyclic esters are called lactones, regardless of whether they are derived from an organic or inorganic acid. One example of an organic lactone is γ-valerolactone.Computed Properties of C14H24O2

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Multi-target-directed design, syntheses, and characterization of fluorescent bisphosphonate derivatives as multifunctional enzyme inhibitors in mevalonate pathway was written by Gao, Jinbo;Liu, Jinggong;Qiu, Yongge;Chu, Xiusheng;Qiao, Yuqin;Li, Ding. And the article was included in Biochimica et Biophysica Acta, General Subjects in 2013.Product Details of 37905-02-5 The following contents are mentioned in the article:

Mevalonate pathway is an important cellular metabolic pathway present in all higher eukaryotes and many bacteria. Four enzymes in mevalonate pathway, including MVK, PMK, MDD, and FPPS, play important regulatory roles in cholesterol biosynthesis and cell proliferation. The following methods were used: cloning, expression and purification of enzymes in mevalonate pathway, organic syntheses of multifunctional enzyme inhibitors, measurement of their IC₅₀ values for above four enzymes, kinetic studies of enzyme inhibitions, mol. modeling studies, cell viability tests, and fluorescence microscopy. We report our multi-target-directed design, syntheses, and characterization of two blue fluorescent bisphosphonate derivatives compounds 15 and 16 as multifunctional enzyme inhibitors in mevalonate pathway. These two compounds had good inhibition to all these four enzymes with their IC₅₀ values at nanomolar to micromolar range. Kinetic and mol. modeling studies showed that these two compounds could bind to the active sites of all these four enzymes. The fluorescence microscopy indicated that these two compounds could easily get into cancer cells. Multifunctional enzyme inhibitors are generally more effective than single enzyme inhibitors, with fewer side effects. Our results showed that these multifunctional inhibitors could become lead compounds for further development for the treatment of soft-tissue tumors and hypercholesteremia. This study involved multiple reactions and reactants, such as (2E,6E)-3,7-Dimethyl-8-oxoocta-2,6-dien-1-yl acetate (cas: 37905-02-5Product Details of 37905-02-5).

(2E,6E)-3,7-Dimethyl-8-oxoocta-2,6-dien-1-yl acetate (cas: 37905-02-5) belongs to esters. Carboxylic acid esters of low molecular weight are colourless, volatile liquids with pleasant odours, slightly soluble in water. Cyclic esters are called lactones, regardless of whether they are derived from an organic or inorganic acid. One example of an organic lactone is γ-valerolactone.Product Details of 37905-02-5

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

High-Resolution ¹³C NMR Study of Liquid 2-Ethylhexyl Benzoate Confined to Porous Silica Glasses was written by Zhang, Jing;Jonas, Jiri. And the article was included in Journal of Physical Chemistry in 1994.Product Details of 5444-75-7 The following contents are mentioned in the article:

Natural abundance carbon-13 NMR spin-lattice relaxation times, T₁, and spin-spin relaxation times, T₂, in the model liquid lubricant 2-ethylhexyl benzoate (I), confined to porous silica glasses prepared by the sol-gel process, were measured as a function of pore size at 294 K for pore radius 21-80 Å. In agreement with earlier results for other polar liquids, the two-state fast-exchange model was valid for the spin-relaxation data for I (i.e., the 1/T₁ rates scale as 1/R with pore radius R). The anal. of the 1/T₁ data for each carbon in confined I in terms of the two-state fast-exchange model allowed the calculation of the relaxation rates 1/T_1S for each carbon of I in the surface layer. The comparison of 1/T_1S for each carbon with the 1/T₁ values for individual carbons in bulk I provided information on motional dynamics of I at the liquid/surface interface. The exptl. ¹³C spin-spin relaxation rates 1/T₂ obey the quadratic power law 1/R² for confined I, confirming that at low frequency, the pure geometric confinement effects dominate over surface interaction effects. Addnl. information on the I surface interactions was obtained by carrying out the NMR experiments with surface-modified silica glasses. This study involved multiple reactions and reactants, such as 2-Ethylhexyl benzoate (cas: 5444-75-7Product Details of 5444-75-7).

2-Ethylhexyl benzoate (cas: 5444-75-7) belongs to esters. Esters are widespread in nature and are widely used in industry. In nature, fats are in general triesters derived from glycerol and fatty acids. Esters are responsible for the aroma of many fruits, including apples, durians, pears, bananas, pineapples, and strawberries. Many esters have the potential for conformational isomerism, but they tend to adopt an s-cis (or Z) conformation rather than the s-trans (or E) alternative, due to a combination of hyperconjugation and dipole minimization effects. The preference for the Z conformation is influenced by the nature of the substituents and solvent, if present. Lactones with small rings are restricted to the s-trans (i.e. E) conformation due to their cyclic structure.Product Details of 5444-75-7

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Characterization of odor-active compounds in the head, heart, and tail fractions of freshly distilled spirit from Spine grape (Vitis davidii Foex) wine by gas chromatography-olfactometry and gas chromatography-mass spectrometry was written by Xiang, Xiao-Feng;Lan, Yi-Bin;Gao, Xiao-Tong;Xie, Han;An, Zhao-Yan;Lv, Zhi-Hao;Yin-Shi;Duan, Chang-Qing;Wu, Guang-Feng. And the article was included in Food Research International in 2020.Computed Properties of C15H22O2 The following contents are mentioned in the article:

Differences in key odor-active volatile compounds among the head, heart, and tail fractions of freshly distilled spirits from Spine grape (Vitis davidii Foex) wine were identified for the first time by gas chromatog.-olfactometry and gas chromatog.-mass spectrometry. Results from aroma extract dilution anal. (AEDA) showed that there were 34, 45, and 37 odor-active compounds in the head, heart and tail fractions, resp. Besides, 20, 22, and 17 quantified compounds, resp., showed odor activity values (OAVs) > 1. The head fraction was characterized by fruity, fusel/solvent notes owing to higher concentrations of higher alcs. and esters, while the tail fraction had more intense smoky/animal, sweaty/fatty attributes due to higher concentrations of volatile phenols and fatty acids. Finally, the heart fraction was characterized by Et octanoate, Et hexanoate, Et 3-phenylpropanoate, Et cinnamate, isoamyl alc., guaiacol, 4-ethylguaiacol, 4-vinylguaiacol, 2,3-butanedione, and (E)-β-damascenone. Furthermore, observation of the distillation progress indicated that different volatiles with various b.ps. and solubilities followed diverse distillation patterns: concentrations of most esters, higher alcs., terpenes and C13-norisoprenoids decreased, while concentrations of volatile phenols, fatty acids and some aromatic compounds increased during distillation As a result, their final concentrations in the three distillate fractions varied significantly. This study involved multiple reactions and reactants, such as 2-Ethylhexyl benzoate (cas: 5444-75-7Computed Properties of C15H22O2).

2-Ethylhexyl benzoate (cas: 5444-75-7) belongs to esters. Volatile esters with characteristic odours are used in synthetic flavours, perfumes, and cosmetics. Certain volatile esters are used as solvents for lacquers, paints, and varnishes. Because of their lack of hydrogen-bond-donating ability, esters do not self-associate. Consequently, esters are more volatile than carboxylic acids of similar molecular weight.Computed Properties of C15H22O2

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Effect of mass transfer at the interface of the polymer solution and extruded solvent during the air gap on membrane structures and performances in TIPS process using triple-orifice spinneret was written by Fang, Chuanjie;Rajabzadeh, Saeid;Wu, Hao-Chen;Zhang, Xinyu;Kato, Noriaki;Kunimatsu, Misato;Yoshioka, Tomohisa;Matsuyama, Hideto. And the article was included in Journal of Membrane Science in 2020.Formula: C13H10O3 The following contents are mentioned in the article:

In this study, a combination of exptl. results and mol. dynamics (MD) simulation was employed to understand the mass transfer between the extruded solvent and polymer solution by using a triple-orifice spinneret in the thermally induced phase separation (TIPS) process. Extruding solvent at the outer layer of the extruded polymer solution with different air gap distances controlled the mass transfer before phase separation The progressive change in the phase separation mechanism, from the liquid-liquid to the solid-liquid induced by mass transfer, played a determined role in tailoring the composite-like structure. The moving of polymer or diluent from the bulk solution to the contact interface changed the polymer surface concentration and subsequently affected the membrane surface pore structure. The MD calculation results elucidated the mass transfer of the solvent and the polymer solution, which drastically affected the membrane structure. The formed spherulite-embedded bicontinuous structure clearly improved the membrane water permeation stability from 52 to 98%. On the other hand, by altering the air gap distances, the membrane water permeation flux enhanced in a wide range from 266 to 1429 L m^-2 h^-1 bar^-1. A new relationship between permeation flux and permeation stability was obtained, which can be utilized as a guideline for the engineering of hollow fiber membranes with high and stable permeability in the TIPS process. This study involved multiple reactions and reactants, such as Diphenyl carbonate (cas: 102-09-0Formula: C13H10O3).

Diphenyl carbonate (cas: 102-09-0) belongs to esters. Esters perform as high-grade solvents for a broad array of plastics, plasticizers, resins, and lacquers, and are one of the largest classes of synthetic lubricants on the commercial market. Acyl chlorides and acid anhydrides alcoholysis is another way to produce esters. Acyl chlorides and acid anhydrides react with alcohols to produce esters. Anydrous conditions are recommended since both acyl chlorides and acid anhydrides react with water.Formula: C13H10O3

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Efficient synthesis of isosorbide-based polycarbonate with scalable dicationic ionic liquid catalysts by balancing the reactivity of the endo-OH and exo-OH was written by Wang, Weiwei;Zhang, Yaqin;Yang, Zifeng;Zhang, Zhencai;Fang, Wenjuan;Niu, Donghui;He, Hongyan;Xu, Fei. And the article was included in Green Chemistry in 2021.Category: esters-buliding-blocks The following contents are mentioned in the article:

In this study, a series of high-activity imidazole-based dicationic ionic liquids (DILs) were designed and prepared as efficient catalysts for balancing the reactivity between the endo-hydroxyl group (endo-OH) and the exo-hydroxyl group (exo-OH) of isosorbide (ISO) to synthesize high mol. weight poly(isosorbide carbonate) (PIC). Meanwhile, the thermal performance of PIC was precisely optimized by regulating the chain configuration. When the trace amounts (4.5 x 10^-5 based on the ISO molar amount) of bis-(3-methyl-1-imidazole)-ethylene dibromide ([C₂(Min)₂][Br]₂) were used, the weight average mol. weight (M_w) of PIC reached 98 700 g mol^-1. It could be concluded from the results of the experiment and the stimulation that the high catalytic activity of DILs was attributed to the strong electrostatic interaction between the cation and the substrate and the effective balance of the reactivity of the endo-OH and the exo-OH. Furthermore, we found that the reduction of hydroxyl groups in the terminal groups and the increase of endo-endo (a₁) structure in the repeating unit improved the thermal properties of PIC. Finally, ¹H NMR, Fourier IR spectroscopy, and d. functional theory (DFT) calculations were used to verify the reaction process through anion and cation multi-site synergistic effect and a possible electrophilic-nucleophilic reaction mechanism was successfully obtained. This study involved multiple reactions and reactants, such as Diphenyl carbonate (cas: 102-09-0Category: esters-buliding-blocks).

Diphenyl carbonate (cas: 102-09-0) belongs to esters. Esters typically have a pleasant smell; those of low molecular weight are commonly used as fragrances and are found in essential oils and pheromones. Acyl chlorides and acid anhydrides alcoholysis is another way to produce esters. Acyl chlorides and acid anhydrides react with alcohols to produce esters. Anydrous conditions are recommended since both acyl chlorides and acid anhydrides react with water.Category: esters-buliding-blocks

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Effect of mixed diluents during thermally induced phase separation process on structures and performances of hollow fiber membranes prepared using triple-orifice spinneret was written by Fang, Chuanjie;Rajabzadeh, Saeid;Liu, Wenyi;Wu, Hao-Chen;Kato, Noriaki;Sun, Yuchen;Jeon, Sungil;Matsuyama, Hideto. And the article was included in Journal of Membrane Science in 2020.Safety of Diphenyl carbonate The following contents are mentioned in the article:

In this study, polyvinylidene fluoride hollow fiber membranes were prepared using a triple-orifice spinneret in thermally induced phase separation A solvent, propylene carbonate (PC), was extruded through the outermost layer of the spinneret. Through the use of this method, all the membranes were developed an entirely porous surface with similar pore size and porosity. Using mixed diluents with different concentrations of di-Ph carbonate and PC, the membrane bulk structures were controlled from an entirely bicontinuous network, a combination of bicontinuous and spherulitic structures, to an entirely spherulitic structure. The tailored bulk structures showed significant effects on the permeability, rejection, and mech. strength of the membrane. Furthermore, the membrane sub-layer structure was modified to form different types from the composite-like structure of the combination of the spherulites and bicontinuous network to entirely spherulites, which controlled the membrane permeation stability within an extensive range of 6% to nearly 100%. A change in the polymeric dope solution phase diagram, as well as the interfacial behaviors of the polymeric dope solution and extruded PC, played important roles in appropriately tailoring membrane structures and performances. These novel and solid findings regarding the connections between structures and performances provide an advisable venue for the design of hollow fiber membranes with satisfactory performances. This study involved multiple reactions and reactants, such as Diphenyl carbonate (cas: 102-09-0Safety of Diphenyl carbonate).

Diphenyl carbonate (cas: 102-09-0) belongs to esters. Carboxylic acid esters of low molecular weight are colourless, volatile liquids with pleasant odours, slightly soluble in water. Acyl chlorides and acid anhydrides alcoholysis is another way to produce esters. Acyl chlorides and acid anhydrides react with alcohols to produce esters. Anydrous conditions are recommended since both acyl chlorides and acid anhydrides react with water.Safety of Diphenyl carbonate

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Facile way of dynamically tailoring microporous structures in polyvinylidene fluoride films prepared by thermally induced phase separation was written by Yang, Bin;Chen, Qinting;Ding, Mengya;Pan, Yang;Zhang, Peng;Wang, Shuqing;Qian, Jiasheng;Miao, Jibin;Xia, Ru;Chen, Peng;Shi, You;Tu, Youlei. And the article was included in Journal of Polymer Science (Hoboken, NJ, United States) in 2021.Product Details of 102-09-0 The following contents are mentioned in the article:

Polyvinylidene fluoride (PVDF) films were prepared via thermally induced phase separation (TIPS) using di-Ph carbonate as the diluter in an attempt to disclose the competitive relationship between crystal growth and droplet growth during phase separation process. By varying the quenching temperature different temperature gradient fields were established, which were theor. evaluated via enthalpy transformation method. The effects of polymer concentration and quenching temperature on evolution of hierarchical morphologies in TIPS films were systematically investigated. According to the morphol. characteristics, the cross-sectional morphol. of the films with lower polymer concentration (Φ_P = 25%) could be divided into three layers; while that of higher polymer concentration counterpart (Φ_P = 55%) only presented a bi-layered structure. The reason for this could be ascribed to the effect of cooling rate on both crystal growth and droplet growth during TIPS process, which further determined the formation of the hierarchical structure in microporous films. With an increasing quenching temperature, both pore size and porosity of PVDF films increased, accompanied by an improvement on both thermal stability and dynamic mech. thermal property. The present study could insightfully supply a facile route to fabricate structure-controllable microporous films of crystalline polymers via an appropriate regulation of the TIPS quenching parameters. This study involved multiple reactions and reactants, such as Diphenyl carbonate (cas: 102-09-0Product Details of 102-09-0).

Diphenyl carbonate (cas: 102-09-0) belongs to esters. Volatile esters with characteristic odours are used in synthetic flavours, perfumes, and cosmetics. Certain volatile esters are used as solvents for lacquers, paints, and varnishes. Liquid esters of low volatility serve as softening agents for resins and plastics. Esters also include many industrially important polymers. Polymethyl methacrylate is a glass substitute sold under the names Lucite and Plexiglas; polyethylene terephthalate is used as a film (Mylar) and as textile fibres sold as Terylene, Fortrel, and Dacron.Product Details of 102-09-0

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Vertical profile and assessment of soil pollution from a typical coking plant by suspect screening and non-target screening using GC/QTOF-MS was written by Liu, Mingyuan;Guo, Changsheng;Zhu, Chaofei;Lv, Jiapei;Yang, Wenlong;Wu, Linlin;Xu, Jian. And the article was included in Science of the Total Environment in 2022.Product Details of 5444-75-7 The following contents are mentioned in the article:

A comprehensive workflow for suspect screening and non-target screening with gas chromatog. coupled with quadrupole time-of-flight mass spectrometry (GC/QTOF-MS) was used to characterize the pollution characteristics of soil samples in a typical coking plant in China. Suspect screening confirmed 57 chems. including PAHs, alkyl PAHs, and phthalates contained in high-resolution personal compound database and library (PCDL). Non-target screening detected 88 chems. from soil samples in the NIST 17 library. A total of 122 chems. were screened in soil samples, and many of them were of emerging concern. Their presence in the soil obtained from coking operations was underestimated, such as the oxygenated PAHs (naphtho[2,1-b]furan and 9H-fluoren-9-one), and the alkyl biphenyls compounds (4,4′-dimethylbiphenyl, 3,3′-dimethylbiphenyl, 4-methyl-1,1′-biphenyl and 2,2′,5,5′-tetramethyl-1,1′-biphenyl). Toxicity assays by luminescent bacteria proved that the extracts from soil samples at different depths showed varying toxicity to V. qinghaiensis sp.-Q67. Soil extracts from a depth of 20-40 cm exhibited the greatest toxicity to luminescent bacteria compared with the other six-layered soil samples, which was correlated with the number of detectable pollutants and total organic carbon content. This study provided a screening method for suspect and non-target contaminants in urban industrial soil sites, which was important in identifying localized contamination sources. This study involved multiple reactions and reactants, such as 2-Ethylhexyl benzoate (cas: 5444-75-7Product Details of 5444-75-7).

2-Ethylhexyl benzoate (cas: 5444-75-7) belongs to esters. Esters perform as high-grade solvents for a broad array of plastics, plasticizers, resins, and lacquers, and are one of the largest classes of synthetic lubricants on the commercial market. Cyclic esters are called lactones, regardless of whether they are derived from an organic or inorganic acid. One example of an organic lactone is γ-valerolactone.Product Details of 5444-75-7

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics