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Sung Yeon Hwang - One of the best experts on this subject based on the ideXlab platform.

Baohua Guo - One of the best experts on this subject based on the ideXlab platform.

  • Synthesis and Characterizations of Poly(Butylene Succinate) Copolyester
    Advanced Materials Research, 2014
    Co-Authors: Li Liu, Li Hai Cai, Dan Liu, Baohua Guo
    Abstract:

    The poly (butylene Succinate) (PBS) and 3 wt% attapulgite (ATP) reinforced PBS/ATP nanocomposites with 1,6-hexanediol were fabricated using an in situ polymerization method. The crystallization behaviors indicated that ATP had effectively acted as nucleating agent, resulting in the enhancement on the crystallization temperature. The SEM results showed a superior interfacial linkage between ATP and PBS. Also, ATP could disperse as a single fiber and embed in the polymer matrix, which resulted in the improved mechanical properties.

  • isomorphism in poly butylene Succinate co butylene fumarate and its application as polymeric nucleating agent for poly butylene Succinate
    Macromolecules, 2012
    Co-Authors: Ruidong Wang, Jin Liu, Baohua Guo
    Abstract:

    Strict isomorphism between butylene Succinate and butylene fumarate in poly(butylene Succinate-co-butylene fumarate) (PBSF) was revealed by DSC and wide-angle X-ray diffraction results. They adopt the same crystal modification, with only a little difference in crystal lattice parameters. The melting point of the copolymer increases linearly with increasing molar ratio of butylene fumarate and the melting enthalpy hardly changes, which meet the requirement of strict isomorphism. The introduction of unsaturated comonomer, fumaric acid, into PBS can enhance the total crystallization rate and the radial growth rate of spherulites. Consequently, PBF and PBSF are highly efficient polymeric nucleating agents for PBS and its copolymers. In this work, strict isomorphism provides us a new method to find polymeric nucleating agent.

  • synthesis characterization and properties of long chain branched poly butylene Succinate
    Journal of Applied Polymer Science, 2012
    Co-Authors: Guoli Wang, Baohua Guo
    Abstract:

    Long-chain branched poly(butylene Succinate) were synthesized through a two-step process of esterification and polycondensation, using 1,2,4-butanetriol (1,2,4-BT) as a long-chain branching agent. The effect of long-chain branches on the crystallization behaviors, rheological properties, and tensile properties was investigated systematically. The results of differential scanning calorimetry and polarized optical microscopy showed that with the increasing of 1,2,4-BT segments, the crystallization temperatures and glass transition temperatures increase slightly, while the relative crystallinity degree decreases gradually. Also, the double-banded extinction patterns with periodic distance along the radial direction were observed in the spherulites of long-chain branched poly(butylene Succinate), similar to that of linear poly(butylene Succinate) (PBS). The result of wide-angle X-ray diffraction indicated that the incorporation of 1,2,4-BT segments had little effect on the crystal structure of PBS. However, based on data from rheology and tensile testing, the viscoelastic properties of long-chain branched PBS under shear flow were different from the linear PBS. For example, the complex viscosities, storage modulus, and loss modulus of long-chain branched PBS at low frequency were significantly enhanced in comparison with those of linear PBS. In addition, long-chain branched PBS showed higher tensile strength than that of linear PBS without notable decrease in the elongation at break when compared with linear PBS. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

  • Synthesis, characterization, and properties of long‐chain branched poly(butylene Succinate)
    Journal of Applied Polymer Science, 2011
    Co-Authors: Guoli Wang, Baohua Guo
    Abstract:

    Long-chain branched poly(butylene Succinate) were synthesized through a two-step process of esterification and polycondensation, using 1,2,4-butanetriol (1,2,4-BT) as a long-chain branching agent. The effect of long-chain branches on the crystallization behaviors, rheological properties, and tensile properties was investigated systematically. The results of differential scanning calorimetry and polarized optical microscopy showed that with the increasing of 1,2,4-BT segments, the crystallization temperatures and glass transition temperatures increase slightly, while the relative crystallinity degree decreases gradually. Also, the double-banded extinction patterns with periodic distance along the radial direction were observed in the spherulites of long-chain branched poly(butylene Succinate), similar to that of linear poly(butylene Succinate) (PBS). The result of wide-angle X-ray diffraction indicated that the incorporation of 1,2,4-BT segments had little effect on the crystal structure of PBS. However, based on data from rheology and tensile testing, the viscoelastic properties of long-chain branched PBS under shear flow were different from the linear PBS. For example, the complex viscosities, storage modulus, and loss modulus of long-chain branched PBS at low frequency were significantly enhanced in comparison with those of linear PBS. In addition, long-chain branched PBS showed higher tensile strength than that of linear PBS without notable decrease in the elongation at break when compared with linear PBS. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

  • poly butylene Succinate and its copolymers research development and industrialization
    Biotechnology Journal, 2010
    Co-Authors: Jun Xu, Baohua Guo
    Abstract:

    Poly(butylene Succinate) (PBS) and its copolymers are a family of biodegradable polymers with excellent biodegradability, thermoplastic processability and balanced mechanical properties. In this article, production of the monomers succinic acid and butanediol, synthesis, processing and properties of PBS and its copolymers are reviewed. The physical properties and biodegradation rate of PBS materials can be varied in a wide range through copolymerization with different types and various contents of monomers. PBS has a wide temperature window for thermoplastic processing, which makes the resin suitable for extrusion, injection molding, thermoforming and film blowing. Finally, we summarized industrialization and applications of PBS.

Xiuli Wang - One of the best experts on this subject based on the ideXlab platform.

  • Synthesis and Properties of Biodegradable Poly(butylene Succinate-co-diethylene glycol Succinate) Copolymers
    Industrial & Engineering Chemistry Research, 2012
    Co-Authors: Jianbing Zeng, Ling Jiao, Yuzhong Wang, Caili Huang, Xiuli Wang
    Abstract:

    Diethylene glycol was incorporated into poly(butylene Succinate) (PBS) to form biodegradable poly(butylene Succinate-co-diethylene glycol Succinate) (P(BS-co-DEGS)) copolymer through a two-step pro...

  • synthesis and properties of biodegradable poly butylene Succinate co diethylene glycol Succinate copolymers
    Industrial & Engineering Chemistry Research, 2012
    Co-Authors: Jianbing Zeng, Ling Jiao, Xi Lu, Yuzhong Wang, Caili Huang, Xiuli Wang
    Abstract:

    Diethylene glycol was incorporated into poly(butylene Succinate) (PBS) to form biodegradable poly(butylene Succinate-co-diethylene glycol Succinate) (P(BS-co-DEGS)) copolymer through a two-step procedure of esterification and polycondensation from succinic acid with 1,4-butanediol and diethylene glycol. The chemical structure of P(BS-co-DEGS) was confirmed by proton nuclear magnetic resonance spectroscopy (1H NMR). The effect of incorporated DEGS content on the molecular weight, thermal properties, crystallization behaviors, and hydrophilicity of the copolymers was investigated by gel permeation chromatography (GPC), differential scanning calorimetry (DSC), wide-angle X-ray diffraction (WAXD), thermogravimetry analysis (TGA), and water contact angle. The mechanical properties and hydrolytic degradation behaviors of P(BS-co-DEGS) were also studied. The results suggest that with an increase of DEGS content, the crystallizability and degree of crystallinity of the copolymers decreased, while the crystal stru...

  • A new biodegradable copolyester poly(butylene Succinate-co-ethylene Succinate-co-ethylene terephthalate)
    Acta Materialia, 2004
    Co-Authors: Li-min Deng, Xiuli Wang, Yuzhong Wang, Ke-ke Yang, Qian Zhou, Song-dong Ding
    Abstract:

    Abstract To obtain a biodegradable polymer material with satisfactory thermal properties, higher elongation and modulus of elasticity, a new copolyester, poly(butylene Succinate-co-ethylene Succinate-co-ethylene terephthalate) (PBEST), was synthesized via direct polycondensation from three prepolymers of butylenes Succinate, ethylene Succinate and ethylene terephthalate (ET). The resulting copolyesters, PBEST, were characterized by 1H-NMR, DSC, TG and WAXRD, and their melting temperature (Tm), melting heat of fusion (ΔHm), glass-transition temperature (Tg), and thermal decomposition temperature (Td) (1.5 wt%) were obtained. Compared to poly(butylene Succinate-co-ethylene Succinate) (PBES), PBEST has improved thermal properties such as higher Tm and Td due to the incorporation of poly(ethylene terephthalate) unit into the main chains of copolyesters, but very low crystallization speeds. The degradation test of copolyesters in a compost condition shows that the degradability of PBEST is as a function of content of ET.

Yuzhong Wang - One of the best experts on this subject based on the ideXlab platform.

  • properties regulation of poly butylene Succinate ionomers through their ionic group distribution
    Polymer, 2015
    Co-Authors: Sichong Chen, Yuzhong Wang, Jianbing Zeng
    Abstract:

    Abstract Dihydroxyl terminated poly(butylene Succinate) ionomer precursors (Pre-PBSIs) with different ionic group contents were prepared to chain-extend with dihydroxyl terminated poly(butylene Succinate) to synthesize high molecular weight poly(butylene Succinate) ionomers (PBSIs) with controlled ionic group distributions. The chemical structures and molecular weights of the precursors and PBSIs were characterized by nuclear magnetic resonance spectroscopy and gel permeation chromatography. The effect of ionic group distribution on the morphology, thermal behavior, isothermal crystallization kinetics, rheological behavior, and mechanical properties of PBSIs were investigated by transmission electron microscopy (TEM), differential scanning calorimeter (DSC), polarizing optical microscopy (POM), wide angle X-ray diffraction (WAXD), rotational rheometer, and tensile testing. With the increase of ionic group content in incorporated Pre-PBSI, phase separation between PBSI and PBS segments occurred as observed by TEM, the crystallization was improved as investigated by DSC and WAXD, while the complex viscosity and tensile strength decreased as studied by rotational rheometer and tensile testing. All the results indicated that the properties of PBSI can be regulated by the ionic group distribution.

  • non isothermal crystallization kinetics of biodegradable poly butylene Succinate co diethylene glycol Succinate copolymers
    Thermochimica Acta, 2013
    Co-Authors: Changlian Xu, Jianbing Zeng, Shaolong Li, Yuzhong Wang
    Abstract:

    Abstract We have modified the properties of biodegradable poly(butylene Succinate) (PBS) by incorporation of diethylene glycol to form poly(butylene Succinate-co-diethylene glycol Succinate) (P(BS-co-DEGS)) copolymers and investigated the fundamental properties and isothermal crystallization behaviors of P(BS-co-DEGS) in previous study. The non-isothermal crystallization is also important for the practical use since they are usually processed under non-isothermal conditions. Therefore, in the present paper we exclusively investigated the non-isothermal crystallization kinetics of P(BS-co-DEGS) and compared with that of neat PBS using differential scanning calorimeter. Three classical methods including Avrami, Ozawa, and Mo's equations have been used to analyze the non-isothermal crystallization kinetics of neat PBS and P(BS-co-DEGS) copolymers. The results suggest that both Avrami and Mo's methods are suitable while Ozawa method is not suitable to describe the non-isothermal crystallization of the polymers. The crystallization rate decreased gradually with increase in the content of DEGS while the crystallization mechanism almost kept unchanged. The non-isothermal crystallization activation energies were evaluated by Vyazovkin method and the results are in accordance with those obtained by other methods.

  • Synthesis and Properties of Biodegradable Poly(butylene Succinate-co-diethylene glycol Succinate) Copolymers
    Industrial & Engineering Chemistry Research, 2012
    Co-Authors: Jianbing Zeng, Ling Jiao, Yuzhong Wang, Caili Huang, Xiuli Wang
    Abstract:

    Diethylene glycol was incorporated into poly(butylene Succinate) (PBS) to form biodegradable poly(butylene Succinate-co-diethylene glycol Succinate) (P(BS-co-DEGS)) copolymer through a two-step pro...

  • synthesis and properties of biodegradable poly butylene Succinate co diethylene glycol Succinate copolymers
    Industrial & Engineering Chemistry Research, 2012
    Co-Authors: Jianbing Zeng, Ling Jiao, Xi Lu, Yuzhong Wang, Caili Huang, Xiuli Wang
    Abstract:

    Diethylene glycol was incorporated into poly(butylene Succinate) (PBS) to form biodegradable poly(butylene Succinate-co-diethylene glycol Succinate) (P(BS-co-DEGS)) copolymer through a two-step procedure of esterification and polycondensation from succinic acid with 1,4-butanediol and diethylene glycol. The chemical structure of P(BS-co-DEGS) was confirmed by proton nuclear magnetic resonance spectroscopy (1H NMR). The effect of incorporated DEGS content on the molecular weight, thermal properties, crystallization behaviors, and hydrophilicity of the copolymers was investigated by gel permeation chromatography (GPC), differential scanning calorimetry (DSC), wide-angle X-ray diffraction (WAXD), thermogravimetry analysis (TGA), and water contact angle. The mechanical properties and hydrolytic degradation behaviors of P(BS-co-DEGS) were also studied. The results suggest that with an increase of DEGS content, the crystallizability and degree of crystallinity of the copolymers decreased, while the crystal stru...

  • A new biodegradable copolyester poly(butylene Succinate-co-ethylene Succinate-co-ethylene terephthalate)
    Acta Materialia, 2004
    Co-Authors: Li-min Deng, Xiuli Wang, Yuzhong Wang, Ke-ke Yang, Qian Zhou, Song-dong Ding
    Abstract:

    Abstract To obtain a biodegradable polymer material with satisfactory thermal properties, higher elongation and modulus of elasticity, a new copolyester, poly(butylene Succinate-co-ethylene Succinate-co-ethylene terephthalate) (PBEST), was synthesized via direct polycondensation from three prepolymers of butylenes Succinate, ethylene Succinate and ethylene terephthalate (ET). The resulting copolyesters, PBEST, were characterized by 1H-NMR, DSC, TG and WAXRD, and their melting temperature (Tm), melting heat of fusion (ΔHm), glass-transition temperature (Tg), and thermal decomposition temperature (Td) (1.5 wt%) were obtained. Compared to poly(butylene Succinate-co-ethylene Succinate) (PBES), PBEST has improved thermal properties such as higher Tm and Td due to the incorporation of poly(ethylene terephthalate) unit into the main chains of copolyesters, but very low crystallization speeds. The degradation test of copolyesters in a compost condition shows that the degradability of PBEST is as a function of content of ET.

Stéphane Marais - One of the best experts on this subject based on the ideXlab platform.

  • Water Transport Properties of Poly(butylene Succinate) and Poly[(butylene Succinate)-co-(butylene adipate)] Nanocomposite Films: Influence of the Water-Assisted Extrusion Process
    The Journal of Physical Chemistry C, 2017
    Co-Authors: Sébastien Charlon, Nadège Follain, Jérémie Soulestin, Michel Sclavons, Stéphane Marais
    Abstract:

    Poly(butylene Succinate) (PBS) and poly[(butylene Succinate)-co-(butylene adipate)] (PBSA)-based composite films loaded with 5 wt % of fillers (native or organo-modified montmorillonites) were extruded using a standard protocol or assisted by water injection. In the resulting composite films, the filler morphology was altered, as evidenced by TEM images. The CNa aggregates were broken with the help of water injection, and the exfoliation/dispersion levels of C30B were dependent on the matrix. By considering the degree of crystallinity of the polymer matrix, the nature of the fillers, and also the processing conditions, the film (micro)structure was successfully correlated to the water (liquid and vapor) behavior of the PBS- and PBSA-based films, studied by means of sorption and permeation measurements. The water permeability and diffusivity were significantly reduced even with an increased water sorption, depending on the matrix and the clay morphology or nature. Specifically, concomitant effects such as ...

  • Influence of crystallinity on the dielectric relaxations of poly(butylene Succinate) and poly[(butylene Succinate)-co-(butylene adipate)]
    European Polymer Journal, 2016
    Co-Authors: Sébastien Charlon, Laurent Delbreilh, Eric Dargent, Nadège Follain, Jérémie Soulestin, Stéphane Marais
    Abstract:

    Abstract Amorphous and semi-crystalline poly(butylene Succinate) (PBS) and poly[(butylene Succinate)-co-(butylene adipate)] (PBSA) are studied with Differential Scanning Calorimetry and Broadband Dielectric Spectroscopy (BDS). It was shown that 21 mol% of butylene adipate group decreases drastically the degree of crystallinity and the size of the crystal lamellae of the PBSA. For the two semi-crystalline polymers, the microstructure is well described by a three-phase model including a small degree of rigid amorphous fraction. Fragility indexes of the main dielectric relaxation are identical for each sample which shows similar segmental dynamics of their amorphous phase. BDS allows detecting complex secondary relaxations in semi-crystalline PBS and PBSA. Local motions are impacted by the microstructure and a new relaxation occurs in more constrained amorphous environments. Correlations between molecular mobility and barrier properties are proposed.

  • Structure–barrier property relationship of biodegradable poly(butylene Succinate) and poly[(butylene Succinate)-co-(butylene adipate)] nanocomposites: influence of the rigid amorphous fraction
    Physical chemistry chemical physics : PCCP, 2015
    Co-Authors: Sébastien Charlon, Eric Dargent, Jérémie Soulestin, Stéphane Marais, M. Sclavons, Nadège Follain
    Abstract:

    Composites composed of polyesters, poly(butylene Succinate) (PBS) or poly[(butylene Succinate)-co-(butylene adipate)] (PBSA), and 5 wt% of montmorillonite (CNa) or organo-modified montmorillonite (C30B) were melt-processed and transformed into films by either compression-molding or extrusion-calendering. XRD, rheological measurements and TEM images clearly indicated that films containing CNa are microcomposites, while nanocomposites were observed for those containing C30B. Using Flash DSC, it was possible, for the first time, not only to measure the heat capacity step at the glass transition of these two materials in their amorphous state, but also to investigate whether the preparation technique influenced the Rigid Amorphous Fraction (RAF) in our PBS- and PBSA-based nanocomposites. In this work, we have successfully shown the correlation between the microstructure of the films and their barrier properties, and especially the role played by the RAF. Indeed, the lowest permeabilities to gases and to water were determined in the films containing the highest RAF in both PBS- and PBSA-based materials.