Phase and optical behaviours of chiral-azo liquid crystal polymethylsiloxanes with isosorbide units

Ma, Ya-Ru; He, Xiaodong; Ye, Cong; Zhang, Baoyan; Liu, Zeping; Wang, Jiwei; Jia, Ying‐Gang

doi:10.1080/02678292.2019.1673843

Cited by 9 publications

(3 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As is well-known, conventional PC is synthesized from diphenyl carbonate (DPC) and BPA, and both of them are derived from petroleum and have chronic toxicity. − Compared with PC synthesized by BPA monomer, poly(isosorbide carbonate) (PIC) is not only green and nontoxic but also has superior optical properties and outstanding resistance to scratch and heat. , At present, synthesis of PIC by melt polycondensation of ISB and DPC has aroused widespread attention; however, substituting DPC by dimethyl carbonate (DMC) would be more ideal from a perspective of green chemistry. The reasons are as follows.…”

Section: Introductionmentioning

confidence: 99%

Cost-Effective Synthesis of High Molecular Weight Biobased Polycarbonate via Melt Polymerization of Isosorbide and Dimethyl Carbonate

Yang

Liu

et al. 2020

ACS Sustainable Chem. Eng.

View full text Add to dashboard Cite

Green synthesis of poly(isosorbide carbonate) (PIC) with remarkable properties is a huge challenge in industrial applications due to low molecular weight and harsh reaction conditions. We reported a novel pathway to synthesize high molecular weight PIC through melt polymerization of isosorbide (ISB) and dimethyl carbonate (DMC), which are derived from the biomass and CO2, respectively. The effects of metal ion-containing compound catalyst on chemical structures, terminal groups, and molecular weight of PIC in the process of melt polycondensation were studied. Compared with the best reported catalyst lithium acetylacetonate, the weight-average molecular weight (M w) of PIC was increased by using our preferred catalyst sodium tert-butoxide from 46 500 to 55 100 with the ISB conversion up to 99.0%, and the reaction time was decreased from 12 h to only 2.5 h, as far as we know, which is the highest M w value and the most efficient catalyst achieved by one-step method. According to the results of the experiment and simulation, we found that high catalytic performance was ascribed to the weak interaction energy of anion–cation of catalyst and the strong proton acceptance ability of the anion of the catalyst. Meanwhile, increasing the interaction energy of anion–cation of the catalyst could inhibit the occurrence of the methylation side reaction and interestingly the activated endohydroxyl groups of ISB were found to be more easily methylated. Finally, based on the captured and detected intermediates of the two-stages of the reaction, a possible mechanim for the synergetic effects of cation–anion through hydrogen bond formation was proposed.

show abstract

Section: Introductionmentioning

confidence: 99%

Cost-Effective Synthesis of High Molecular Weight Biobased Polycarbonate via Melt Polymerization of Isosorbide and Dimethyl Carbonate

Yang

Liu

et al. 2020

ACS Sustainable Chem. Eng.

View full text Add to dashboard Cite

show abstract

“…3,4 Isosorbide (IS) is a chiral and rigid V-shaped compound with two hydroxyl groups in internal and external configurations and regarded as an ideal alternative to BPA due to its excellent rigidity, chiral, and nontoxic properties. [5][6][7] Compared with the traditional BPA-based PC, the nontoxic and environmentally friendly poly(isosorbide carbonate) (PIC) has superior optical properties and outstanding weatherability (UV stability), 5,8,9 so it has a good application prospect in the field of food packaging. 6 Usually, PIC was synthesized mainly by the melt polycondensation of IS with diphenyl carbonate (DPC) or dimethyl carbonate (DMC).…”

Section: ■ Introductionmentioning

confidence: 99%

“…Polycarbonate (PC), as a thermoplastic engineering plastic, has been widely applied in electronics, automotive industries, medical equipment, food packaging, aerospace, and so forth because of its unique thermal, mechanical, and optical properties. , Bisphenol A (BPA), the monomer of traditional PC, is derived from petroleum and can cause endocrine disorders and harm health. For sustainable development and safety considerations, a wide range of biobased polycarbonates has become an urgent need. , Isosorbide (IS) is a chiral and rigid V-shaped compound with two hydroxyl groups in internal and external configurations and regarded as an ideal alternative to BPA due to its excellent rigidity, chiral, and nontoxic properties. - Compared with the traditional BPA-based PC, the nontoxic and environmentally friendly poly(isosorbide carbonate) (PIC) has superior optical properties and outstanding weatherability (UV stability), ,, so it has a good application prospect in the field of food packaging …”

Section: Introductionmentioning

confidence: 99%

Efficient Synthesis of High-Molecular-Weight Biobased Polycarbonates by Lithium Lactate

Wang,

Quan

et al. 2023

ACS Appl. Polym. Mater.

View full text Add to dashboard Cite

Biobased polycarbonates have attracted a wide range of interest due to sustainable resources; however, the synthesis of biobased polycarbonates with a high molecular weight remains a great challenge on account of the influence of catalysts. Herein, biobased poly(isosorbide carbonate) (PIC) with a high molecular weight of 105.0 kDa and excellent light transparency was synthesized via melt polycondensation of isosorbide and diphenyl carbonate by an efficient lithium lactate catalyst under mild conditions, including a short transesterification time of 0.5 h at a low reaction temperature of 150 °C, followed by polycondensation at 200 °C for 1 h. Furthermore, the structures of reaction intermediates and polymers were characterized, and the catalytic mechanism was elucidated by density functional theory calculations. Such a low-cost commercial catalyst would have a broad application prospect in the industrial production of PIC.

show abstract

Asymmetric chiral disazo dopants with high anisotropy for versatile modulation of liquid crystal optics

Liao

Feng

Zhang

et al. 2022

Journal of Molecular Liquids

View full text Add to dashboard Cite

Phase and optical behaviours of chiral-azo liquid crystal polymethylsiloxanes with isosorbide units

Cited by 9 publications

References 43 publications

Cost-Effective Synthesis of High Molecular Weight Biobased Polycarbonate via Melt Polymerization of Isosorbide and Dimethyl Carbonate

Cost-Effective Synthesis of High Molecular Weight Biobased Polycarbonate via Melt Polymerization of Isosorbide and Dimethyl Carbonate

Efficient Synthesis of High-Molecular-Weight Biobased Polycarbonates by Lithium Lactate

Asymmetric chiral disazo dopants with high anisotropy for versatile modulation of liquid crystal optics

Contact Info

Product

Resources

About