Copolyester Poly Research Articles

Water-soluble biodegradable polyesters with pH and ionic responsivity

The synthesis of novel water-soluble polymers with biodegradability is an effective way to mitigate their negative environmental impacts. In this study, semi-aromatic copolyester poly(butylene succinate-co-butylene terephthalate) (PBST) with exceptional biodegradability is used as the resin matrix. Anionic sodium 1–3-isophthalate-5-sulfonate (SIPA) is introduced as a fourth monomer to prepare random poly(butylene succinate-co-butylene terephthalate-co-butylene 5-sodiosulfoisophthalate) (PBSTS) copolyesters by melt copolymerization. The incorporation of ionic groups enhances the hydrophilicity and water absorption of the copolyesters, resulting in water-soluble materials that exhibit ionic and temperature responsivity. Furthermore, the ionized biodegradable copolyesters demonstrate distinct pH-dependent degradation, which is accelerated at pH = 5.5 and 8.5 but inhibited at pH = 7.2. Degradation assessments in simulated body fluids reveal that the PBSTS copolyesters exhibit significant degradation in gastric fluids at pH = 1.5 with minimal degradation in intestinal fluids at pH = 6.8 and in body fluids at pH = 7.0. This unique degradation performance highlights the potential of these materials for addressing the challenges associated with selective drug delivery and localized controlled release in the human body.

Synthesis and Characterization of Poly(butylene glycol adipate-co-terephthalate/diphenylsilanediol adipate-co-terephthalate) Copolyester.

The copolyester poly(butylene glycol adipate-co-terephthalate/diphenylsilanediol adipate-co-terephthalate) (PBDAT) was synthesized by the melt polycondensation method using terephthalic acid, adipic acid, 1,4-butanediol, and diphenylsilylene glycol as the raw materials. The molecular chain structure, thermal properties, thermal stability, mechanical properties, and degradation behaviors of the copolyesters were investigated. The results showed that the prepared PBDAT copolyesters exhibited good thermal stability and mechanical properties. With the increase in diphenylsilanediol (DPSD) content, the thermal stability of PBDAT and the melting temperature both increased. The tensile strength and elastic modulus of PBDAT also exhibited an increasing tend. When the DPSD content was 12.5% (PBDAT-12.5), the tensile strength, the elastic modulus, and elongation at break were 30.56 MPa, 238 MPa, and 219%, respectively. With the increase in diphenylsilanediol content, the hydrophilicity of PBDAT decreased, but PBDAT still shows good degradability and the thermal degradation T5% temperature was 355 °C. The thermal degradation of PBDAT was also improved.

Synthesis, Properties, and Degradation of Poly(butylene succinate-co-sebacicate-co-salicylicate) Copolyesters

Since monomers in backbone of poly(butylene succinate-co-adipate) (PBSA) are not entirely derived from bio-based sources, limiting its application in the face of increasingly stringent environmental policies. In this study, a novel full bio-based biodegradable random copolyester poly(butylene succinate-co-sebacicate-co-salicylicate) was successfully synthesized. Detailed investigations were conducted on the structural, mechanical, and degradation characteristics resulting from the introduction of salicylicate and sebacicate units. Introduction of salicylicate units effectively enhanced the mechanical performance. In comparison to PBSA, the tensile modulus of copolymer increased by 20.2% with 10% salicylic acid. Introduction of sebacicate units significantly altered the crystalline structure of copolymer and promote the degradation efficiency. Considering both mechanical strength and degradation efficiency, the copolyester with 2% salicylic acid and 20% sebacic acid was found to meet practical application requirements. Relative to PBSA, this copolymer demonstrated a 13.7% increase in tensile modulus and a remarkable 143.1% improvement in degradation efficiency. Importantly, this study focused on the effect of the bio-based rigid monomer salicylic acid and the soft monomer sebacic acid on the degradability of biodegradable polymers. The insights gained provide valuable guidance for tailoring the synthesis of degradable plastics to meet diverse degradation cycle requirements.

Synthesis and characterization of biphenyldicarboxylic acid-modified poly(1,4-cyclohexylenedimethylene terephthalate) copolyesters

A new copolyesters of poly(1,4-cyclohexylenedimethylene terephthalate-co-4,4’-biphenydicarboxylate) (PCTB) with different compositions were synthesized from terephthalic acid, 1,4-cyclohexanedimethanol and 4,4’-biphenyldicarboxylic acid (BDA) via esterification-polycondensation reaction. The synthesized copolyesters were analyzed by 1H-NMR, 13C-NMR, FT-IR, GPC, intrinsic viscosity, DSC, TGA and tensile testing, respectively. The 1H-NMR, 13C-NMR and FT-IR results verify the successful introduction of BDA into poly(1,4-cyclohexylenedimethylene terephthalate (PCT) chains. The introduction of BDA into PCT chains can effectively lower the melting point of PCT, making it easier to process. The glass transition temperature of PCTB is higher than 103 °C and its thermal stability is better than that of PCT. The rheological tests confirm the enhanced melting stability of PCT after introducing BDA into PCT chains. Furthermore, the PCTB, which owns the comparable mechanical properties to PCT, is a tough polymer with the higher Young’s modulus (above 230 MPa), the higher tensile strength (above 41 MPa) and the higher elongation at break (above 159%).

Synthesis, Characterisation and Cytotoxic Activity of Random Copolyester using 1,4- Dithiane- 2,5-diol

A novel random copolyester Poly(1,4-dithiane-2,5-diol Succinate – Co – 1,2-ethane diol Succinate) PDES containing sulphur atom was synthesised by direct melt polycondensation method using 1,4- dithiane-2,5-diol as a special monomer, succinic acid, and 1,3 ethane diol with Titanium tetra isopropoxide as catalyst. The wide range of application of the special monomer especially as biocontrol material and food additive led us to extend our area of research towards producing copolyester with cytotoxic activity. The various physical properties of the copolyester such as inherent viscosity, glass transition temperature, solubility and crystalline nature was investigated and studied in detail.The 1H-NMR and FT-IR was done to investigate the chemical properties of the PDES copolyester.In Vitro cytotoxicity against Normal (Vero cell line) and cancer (A549 Lung cancer cell line) by MTT Assay, Antioxidant activity by Dot-Blot/DPPH scavenging Assay and Antimicrobial by Well diffusion method studies proved that the synthesised copolyester have immense biological properties and could be used in biomedical application.

3, 3’-thiodipropionic acid: A versatile monomer to synthesis aliphatic random copolyesters with biological applications

A prime monomer 3,3’-thiodipropionic acid was mixed with other monomers such as 1,4 butanediol and 1,4 butanedioic acid to produce aliphatic random copolyester Poly(butylthiodipropionate-co-butylbu tanedioate) (PBTBB) by direct melt polycondensation method. The physical properties such as solubility by solubility test, inherent viscosity by Ubbelohde viscometer, Tg by differential scanning colorimetry (DSC) and the crystalline nature by X-ray diffraction (XRD) technique of synthesized polymer were investigated. The chemical structure of the obtained copolyester was studied by FTIR, 1H-NMR and 13CNMR spectroscopy. To resolve the biological applications, the synthesized copolyester was tested for human pathogenic bacteria using well diffusion method, in vitro cytotoxicity against normal Vero cell line, A549 lung cancer cell line by MTT assay and in vitro antioxidant property studied by Dot-Blot assay.

WITHDRAWN: Synthesis and characterization of random copolymerization of aliphatic biodegradable reunite D-Mannitol

Two new random copolyesters Poly(mannitol sebacate-co– mannitol citrate) (PMSeC) and Poly(mannitol azelate-co-mannitol citrate) (PMAC), were synthesized by direct liquefy polycondensation method using Titanium tetra isopropoxide as a catalyst. The structural arrangement of synthesized polyesters was confirmed by various spectral analysis such as FT-IR, 1 H NMR and 13 C NMR spectroscopy. The crystalline nature of prepared materials was determined by X-Ray Diffraction and Differential scanning calorimetry techniques. The biodegradable ability was confirmed by weight loss methodology. All the synthesized polyesters shows efficient biodegradability which is very useful in drug delivery, Tissue Engineering, Biomedical application, Drug loaded and eco- friendly packaging materials.

Poly(butylene succinate-co-butylene acetylenedicarboxylate): Copolyester with Novel Nucleation Behavior.

Big spherulite structure and high crystallinity are the two main drawbacks of poly(butylene succinate) (PBS) and hinder its application. In this work, a new type of copolyester poly(butylene succinate-co-butylene acetylenedicarboxylate) (PBSAD) is synthesized. With the incorporation of acetylenedicarboxylate (AD) units into PBS chains, the crystallization temperature and crystallinity are depressed by excluding AD units to the amorphous region. In contrast, the primary nucleation capability is significantly strengthened, without changing the crystal modification or crystallization kinetics, leading to the recovery of total crystallization rate of PBSAD under the same supercooling condition. The existence of specific interaction among AD units is found to be crucial. Although it is too weak to contribute to the melt memory effect at elevated temperature, the interaction continuously strengthens as the temperature falls down, and the heterogeneous aggregation of AD units keeps growing. When the aggregating process reaches a certain extent, it will induce the formation of a significant amount of crystal nuclei. The unveiled nucleation mechanism helps to design PBS copolymer with good performance.

Partially bio-based copolyesters poly(ethylene 2,5-thiophenedicarboxylate-co-ethylene terephthalate): Synthesis and properties

The aim of this study was to investigate the feasibility of replacing petroleum-based terephthalic acid (PTA) with renewable 2,5-thiophenedicarboxylic acid (TDCA) in poly(ethylene terephthalate) (PET), a series of copolyesters were synthesized from PTA, TDCA and ethylene glycol (EG). The effects of composition on structures, thermal properties, mechanical properties and β relaxation were studied. With the increase of the TDCA content, the esterification reaction time is noticeably shorter in the first step because the acidity of TDCA is stronger. PET, PETF and PETTF25 are semi-crystalline materials. However, no melting and crystallization peaks were observed for PETTF49 and PETTF74. All polyesters exhibit high tensile strength (56.0–68.8 MPa) and good toughness (elongation at break: 190–508%). With the increase of the TDCA content, β relaxation peak is shifted to a higher temperature. For all PET, PETF, and PETTFs, high peak intensity of the β relaxation can be achieved, indicating that the motions of more units are believed to contribute to the relaxation behavior.

Bio-based copolyesters poly(butylene 2,6-naphthalate-co-butylene furandicarboxylate) derived from 2,5-furandicarboxylic acid (FDCA): Synthesis, characterization, and properties

A series of copolymers poly(butylene 2,6-naphthalate-co-butylene furandicarboxylate) (PBNFs) derived from 2,5-furandicarboxylic acid (FDCA) were synthesized. The molecular weight, microstructures, thermal and mechanical properties were characterized. DSC results show that PBN and PBNF25 can crystallize rapidly. However, the crystallization rates of PBNF50, PBNF75 and PBF are very slow. The Td,5% and Td,max values of all polyesters were higher than 360 °C and 390 °C, respectively. Compared with PBN, PBNF25, PBNF50, PBNF75 and PBF exhibited much higher elongation at break (214–295%) and bio-based content (46–100%).

Modulated crystallization behavior of bacterial copolyester poly(3-hydroxybutyrate-co-3-hydroxyhexanoate): Effect of a linear multiple amides derivative as a nucleator

A multiple amides-based linear organic compound (TMC-300) was synthesized and as an efficient nucleator was incorporated into PHBH to fabricate PHBH/TMC-300 composite to investigate effect of TMC-300 on crystallization behavior of PHBH in-depth. Nucleation capacity of TMC-300 on the PHBH is significantly higher than those of two conventional inorganic nucleators. TMC-300 exhibits dual effects on crystallization behavior of PHBH in terms of its weight fraction (fTMC-300). Low fTMC-300 increased substantially crystallization rate, crystallinity and crystal density, and decreased greatly crystallization time of PHBH, but relative higher fTMC-300 hindered slightly crystallization process. Hydrogen bond interaction exists between PHBH and TMC-300 and facilitates excellent dispersion of TMC-300 in PHBH matrix. In-situ FTIR measurement suggests that hydrogen interaction hindered reorganization of ester bond in crystallization process of PHBH. Mechanisms on nucleation of PHBH and effect of TMC-300 on crystallization behavior of PHBH, are proposed and discussed.

Synthesis, Characterization and in vitro Antimicrobial, Antioxidant and Anticancer Activity of Random Copolyester Using 1,4-Dithiane-2,5-diol

A random copolyester was prepared by direct melt polycondensation method using 1,4-dithiane-2,5-diol, 1,4-cyclohexane diol and Sebacic acid in the mole ratio 1:1:2 using titanium tetra isopropoxide as catalyst. The synthesized copolyester poly(1,4-dithiane-2,5-diol sebacate–co–1,4-cyclohexane diol sebacate) (PDCSe) was characterized by FT-IR, 1H NMR and 13C NMR to determine the chemical structure, while wide angle XRD, differential scanning spectroscopy and Inherent viscosity were determined to study its physical properties. Further the antioxidant, antimicrobial and anticancer activities of the synthesized copolyester were determined to study its biological property.

New bio-based copolyesters poly(trimethylene 2,5-thiophenedicarboxylate-co-trimethylene terephthalate): Synthesis, crystallization behavior, thermal and mechanical properties

A series of copolyesters based on poly(trimethylene terephthalate) derived from 2,5-thiophenedicarboxylic acid (TFDCA) have been successfully synthesized by the melting polymerization. Microstructures and molecular weights were characterized by 1H NMR and size exclusion chromatography (SEC), respectively. Meanwhile, thermal properties, crystallization behaviors, and crystal structures were investigated by DSC, TGA, and WAXD. The results confirmed the copolymer compositions were nearly equal to the feed compositions. The weight molecular weights were all higher than 21000 g/mol for all polyesters synthesized. With increasing the TFDCA content, the glass transition temperature decreased slightly due to the weaker rigidity of the thiophene ring. DSC and WAXD results demonstrated that the isodimorphic behavior occurred for poly(trimethylene 2,5-thiophenedicarboxylate-co-trimethyleneterephthalate)s (PTTTFs). When TFDCA content was 25%, PTTTF25 exhibited the moderate tensile strength (53.1 MPa). However, the high elongation at break (396%) was observed due to the β relaxation and strain-induced crystallization.

Synthesis and characterization of poly(isosorbide-co-butylene 2,5-furandicarboxylate) copolyesters

Fully biobased copolyesters poly(isosorbide-co-butylene 2,5-furandicarboxylate) (PISBF) were synthesized from 2,5-dimethylfuran dicarboxylate (DMFD), isosorbide (IS) and 1,4-butanediol (BDO) via transesterification and polycondensation reactions. The resulting copolymers were characterized by 1H NMR, 13C NMR, GPC, intrinsic viscosity, DSC, TGA and tensile testing, respectively. The NMR characterizations had confirmed that BDO was successfully introduced into the poly(isosorbide 2,5-furandicarboxylate) (PIF) polyester chains. Over the IS experimental composition range 20–80 % in copolymer chains, PISBF copolymers had TD, 5% values higher than 370 °C and TDM higher than 405 °C, and Tg values within the range of 55 °C and 150 °C. Introduction of BDO units into PIF chains imparted the PISBF copolyester with better mechanical performance than PIF, thus PISBF copolyesters with IS content of 20–50% were strong and toughened copolymers with Young’s modulus about 1400 MPa, tensile strength at break higher than 53 MPa, and elongation at break higher than 46%.

Mechanical properties and heat resistance of stereocomplex polylactide/copolyester blend films prepared by in situ melt blending followed with compression molding

This work focuses on the process to obtain high heat-resistant stereocomplex polylactide (scPLA)/copolyester blend films by in situ melt blending of high molecular-weight poly(L-lactide) (PLLA), low molecular-weight poly(D-lactide) (PDLA) and copolyester followed with compression molding. A copolyester of poly(ε-caprolactone-co-L-lactide) was used as a film former. Stereocomplexation, mechanical properties and heat resistance of the scPLA/copolyester blend films were investigated by differential scanning calorimetry (DSC), tensile testing and dynamic mechanical analysis (DMA), respectively. The PDLA fractions enhanced stereocomplexation and heat resistance of the blend films while the copolyester fraction reduced film brittleness. Dimensional stability to heat of blend films was also determined and was accorded to their DMA results. It was concluded that the high heat-resistant and less brittle scPLA films could be prepared using 70/30 (w/w) PLLA/PDLA with 20 wt% copolyester through melt blending before compression molding. This film showed similar stress at break and heat resistance to those of polypropylene film but with lower strain at break.

Synthesis of polyhydroxyalkanoates through the biodegradation of poly(cis-1,4-isoprene) rubber

The search of alternative substrates for the synthesis of polyhydroxyalkanoates (PHA) has become an important factor in order to decrease the production costs. Therefore, the use of industrial by-products or waste materials as carbon and energy sources for different PHA-producing microorganisms has been evaluated during the last decades. Recombinant strains of Gordonia polyisoprenivorans VH2 harboring plasmid pAK68, which contains phaCAB from Ralstonia eutropha and plasmid pAK71 comprising phaC1 from Pseudomonas aeruginosa were evaluated for PHA production. Cultivations were performed in shake flasks, using different carbon sources under an N-starvation condition. Having in consideration the rubber degrading capability of the actinomycete, poly(cis-1,4-isoprene) was utilized as sole carbon source. After twenty days of cultivation the PHA content was analyzed using GC-MS. In cultures of G.polyisoprenivorans harboring pAK68, the detection of 3-hydroxybutyrate (3HB) and 3-hydroxyvalerate (3HV) monomer units indicated the accumulation of the copolyester poly(3HB-co-3HV). This study proposes a recycling method for rubber waste through its biotransformation into bioplastic.

2,5‐Furandicarboxylic acid as a sustainable alternative to isophthalic acid for synthesis of amorphous poly(ethylene terephthalate) copolyester with enhanced performance

ABSTRACT2,5‐furandicarboxylic acid (FDCA), a bio‐based monomer, was taken as a sustainable alternative to isophthalic acid (IPA) for the modification of poly(ethylene terephthalate) (PET). Results showed that FDCA was more effective than IPA in terms of reducing the crystallization activity of PET, because FDCA is more rigid and highly polar, which will hinder the PET chain packing during crystallization process. Moreover, modification of PET with FDCA resulted in copolyester with higher glass transition temperature, higher tensile modulus, better optical clarity, and gas barrier property, compared to those of IPA. With the addition of 20 mol % FDCA, the resulted copolyester poly(ethylene 2,5‐furandicarboxylate‐co‐ethylene terephthalate) (PEFT 20) was able to keep high transparency even after being annealed at 110 °C for 40 min. However, when 20 mol % of IPA was added, poly(ethylene isophthalate‐co‐ethylene terephthalate) (PEIT20) easily turned opaque under the same heat treatment. Therefore, less amount of FDCA was required in order to obtain the PET copolyester with better performance. The result indicated that FDCA had great potential to substitute IPA for the modification of PET from the point of view of industrial application. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47186.

De Novo Synthesis and Assembly of Flexible and Biocompatible Physical Sensing Platforms

AbstractFlexible physical sensing platforms (PSP) that can detect and communicate with surrounding physical data, such as force, strain, and temperature, are of interest in a variety of high‐tech fields, such as for wearable electronics, soft robotics, and real‐time healthcare monitoring. However, a crucial question remains relative to the design and assembly of PSPs that can meet the multitude of requirements for such devices, such as biocompatibility, stretchability, and high‐sensitivity to the target factor. In this study, a flexible PSP system based on graphene and biodegradable copolyester poly(CL‐co‐TOSUO) (PCT), which is synthesized by ring‐opening copolymerization of ε‐caprolactone (CL) and 1,4,8‐trioxaspiro‐[4,6]‐9‐undecanone (TOSUO). In this PSP system, graphene acts as conductive layer to connect the electrical signals, while the highly‐stretchable linear copolyester with structural transfer temperature (melting temperature of crystals) at 37 °C provides an active substrate to sense moderate mechanical and temperature stimuli. The resultant PCT/graphene PSP features high sensitivity for a manifold of mild surrounding physical stimuli, such as finger touch and movement, sound vibrations, body temperature, and light bulb temperature, showing promising applications in healthcare monitoring, human–machine interface, as well as soft robotics.

Competition and miscibility of isodimorphism and their effects on band spherulites and mechanical properties of poly(butylene succinate-co-cis-butene succinate) unsaturated aliphatic copolyesters

Unsaturated copolyesters poly(butylene succinate-co-cis-butene succinate) (P(BS-co-cBS)) were the first time prepared by polycondensation in combination with stannous octoate as catalyst and 4-methoxyphenol as radical inhibitor, achieving linear random copolyesters with a number-average molecular weight up to 38.2 kg/mol. The cis-2-butene-1, 4-diol used in this work showed a peculiarity of no isomerization or cross-linking side reaction even at high reaction temperatures, due to the high chemical stability of the unconjugated cis-double bond. Isodimorphic behavior between butylene succinate (BS) and cis-butane succinate (cBS) in P(BS-co-cBS) was evidenced by DSC and WAXD analyses. Then, the competition and miscibility of isodimorphism between BS and cBS units were further investigated by thermodynamic analyses. The significant discrepancy in competition and miscibility between BS and cBS units from conformational geometry demonstrated unique physicochemical properties and structure-properties relationships in such system of unsaturated copolyesters. A great impact of competition and miscibility on band spherulites and mechanical properties of the copolyesters was observed and discussed. In conclusion, our work here not only clarifies the effect of cis-double bond on isodimorphism in the unsaturated copolyesters, but also gives an insight into the mechanism of how the competition and miscibility regulates their physical properties.

GBR membrane of novel poly (butylene succinate-co-glycolate) co-polyester co-polymer for periodontal application

In periodontics, osteoconductive biodegradable guided bone regeneration (GBR) membranes with acceptable physico-mechanical properties are required to fix alveolar bone defects. The objectives of the present study were to produce and characterize a novel co-polyester—poly (butylene succinate-co-glycolate) (PBSGL), and fabricate a PBSGL membrane by electrospinning. We then aimed to evaluate the in vitro effect of the glycolate ratio on the biocompatibility and osteogenic differentiation of mesenchymal stem cells (MSCs), and evaluate in vivo bone regeneration using these membranes in rabbit calvarial defects by histology. Increasing the glycolate ratio of electrospun PBSGL membranes resulted in better cell attachment, greater cell metabolic activity, and enhanced osteogenic potential at both transcriptional and translational levels. Histologic and histomorphometric evaluations revealed further that bone defects covered with fibers of higher glycolate ratios showed more bone formation, with no adverse inflammatory response. These results suggest that novel PBSGL electrospun nanofibers show great promise as GBR membranes for bone regeneration.