This study was conducted to determine the influence of the oil palm boiler ash (OPBA) reinforcement on the microstructural, physical, mechanical and thermal properties of epoxy polymer composites. The chemical composition analysis of OPBA revealed that it contains about 55 wt.% of SiO2 along with other metallic oxides and elements. The surface morphology of OPBA showed angular and irregular shapes with porous structures. The influence of OPBA as a reinforcement in epoxy composite was studied with varying filler loadings (10-50 wt.%) and different particle sizes (50-150 μm). The result showed that the incorporation of OPBA in composites has improved the physical, mechanical and thermal properties of the epoxy matrix. The highest physical and mechanical properties of fabricated composites were attained with 30 wt.% loading and size of 50 μm. Also, thermal stability and the percentage of char residue of the composite increased with increasing filler loading. Furthermore, the contact angle of OPBA reinforced epoxy composites increased with the increase of filler loading. The lowest value of the contact angle was obtained at 30 wt.% of filler loading with the OPBA particle size of 50 μm. The finding of this study reveals that the OPBA has the potential to be used as reinforcement or filler as well as an alternative of silica-based inorganic fillers used in the enhancement of mechanical, physical and thermal properties of the epoxy polymer composite.
A bench-scale model of a partially packed upflow anaerobic fixed film (UAF) reactor was set up and operated at five different hydraulic retention times (HRTs) of (17, 14, 10, 8, and 5) days. The reactor was fed with synthetic rubber wastewater consisting of a chemical oxygen demand (COD) concentration of 6355-6735 mg/L. The results were analyzed using the Monod model, the Modified Stover-Kincannon models, and the Grau Second-Order Model. The Grau Second-Order model was found to best fit the experimental data. The biokinetic constant values, namely the growth yield coefficient (Y) and the endogenous coefficient (Kd) were 0.027 g VSS/g COD and 0.1705 d-1, respectively. The half-saturation constant (Ks) and maximum substrate utilization rate (K) returned values of 84.1 mg/L and 0.371 d-1, respectively, whereas the maximum specific growth rate of the microorganism (μmax) was 0.011 d-1. The constants, Umax and KB, of the Stover-Kincannon model produced values of 6.57 g/L/d and 6.31 g/L/d, respectively. Meanwhile, the average second-order substrate removal rate, ks(2), was 105 d-1. These models gave high correlation coefficients with the value of R2 = 80-99% and these indicated that these models can be used in designing UAF reactor consequently predicting the behaviour of the reactor.
Heat explosions are sometimes observed during the synthesis of phenol formaldehyde (PF) resin. This scenario can be attributed to the high latent heat that was released and not dissipated leading to the occurrence of a runaway reaction. The synthesis temperature and time played important roles in controlling the heat release, hence preventing the resin from hardening during the synthesis process. This study aims to assess the rheological and viscoelasticity behaviors of the PF resin prepared using paraformaldehyde. The prepared PF resin was designed for laminate applications. The rheological behavior of the PF resin was assessed based on the different molar ratios of phenol to paraformaldehyde (P:F) mixed in the formulation. The molar ratios were set at 1.00:1.25, 1.00:1.50 and 1.00:1.75 of P to F, respectively. The rheological study was focused at specific synthesis temperatures, namely 40, 60, 80 and 100 °C. The synthesis time was observed for 240 min; changes in physical structure and viscosity of the PF resins were noted. It was observed that the viscosity values of the PF resins prepared were directly proportional to the synthesis temperature and the formaldehyde content. The PF resin also exhibited shear thickening behavior for all samples synthesized at 60 °C and above. For all PF resin samples synthesized at 60 °C and above, their viscoelasticity results indicated that the storage modulus (G'), loss modulus(G″) and tan δ are proportionally dependent on both the synthesis temperature and the formaldehyde content. Heat explosions were observed during the synthesis of PF resin at the synthesis temperature of 100 °C. This scenario can lead to possible runaway reaction which can also compromise the safety of the operators.
The present article evaluates the composition and synthesis of hydrogel beads. Hydrogels, owing to their known biocompatibility, are widely used in drug delivery as a host (or drug carrier). Hydrogels, owing to their physical, chemical and biological properties, are popular in many aspects. Hydrogels are crosslinked-hydrophilic polymers and commercialized/synthesized in both natural and synthetic forms. These polymers are compatible with human tissues, therefore can be potentially used for biomedical treatments. Hydrogels in drug delivery offer several points of interest such as sustainability, and sensitivity without any side-effects as compared to traditional methods in this field. Drugs can encapsulate and release continuously into the targets when hydrogels are activated/modified magnetically or by fluorescent materials. It is crucial to develop new crosslinked polymers in terms of "biocompatibility" and "biodegradability" for novel drug delivery platforms. In the event that the accomplishments of the past can be used into the longer terms, it is exceedingly likely that hydrogels with a wide cluster of alluring properties can be synthesized. The current review, offers an updated summary of latest developments in the nanomedicines field as well as nanobased drug delivery systems over broad study of the discovery/ application of nanomaterials in improving both the efficacy of drugs and targeted delivery of them. The challenges/opportunities of nanomedicine in drug delivery also discussed. SCOPE OF THE RESEARCH: Although several reviews have been published in the field of hydrogels, however many of them have just centralized on the general overviews in terms of "synthesis" and "properties". The utilization of hydrogels and hydrogel-based composites in vital applications have been achieved a great interest. In this review, our aim is to recap of the key points in the field of hydrogels such as; a) hydrogel nanocomposites, b) magnetic beads, c) biomedical applications, and d) drug delivery. In the same vein, these outlines will be expanded with emphasizing on the boon of magnetic beads and recent developments in this area.
Most of the polymers and their blends, utilized in carbon capture membranes, are costly, but cellulose acetate (CA) being inexpensive is a lucrative choice. In this research, pure and mixed matrix membranes (MMMs) have been fabricated to capture carbon from natural gas. Polyethylene glycol (PEG) has been utilized in the fabrication of membranes to modify the chain flexibility of polymers. Multi-walled carbon nanotubes (MWCNTs) provide mechanical strength, thermal stability, an extra free path for CO2 molecules and augment CO2/CH4 selectivity. Membranes of pure CA, CA/PEG blend of different PEG concentrations (5%, 10%, 15%) and CA/PEG/MWCNTs blend of 10% PEG with different MWCNTs concentrations (5%, 10%, 15%) were prepared in acetone using solution casting techniques. Fabricated membranes were characterized using SEM, TGA and tensile testing. Permeation results revealed remarkable improvement in CO2/CH4 selectivity. In single gas experiments, CO2/CH4 selectivity is enhanced 8 times for pure membranes containing 10% PEG and 14 times for MMMs containing 10% MWCNTs. In mix gas experiments, the CO2/CH4 selectivity is increased 13 times for 10% PEG and 18 times for MMMs with 10% MWCNTs. Fabricated MMMs have a tensile strength of 13 MPa and are more thermally stable than CA membranes.
In this study, compatibilizing effects of caprolactam-maleic anhydride (CL-MAH) and
polyethylene-grafted-maleic anhydride (PE-g-MAH) with different blend compositions on polymer
blends of recycled high density polyethylene (RHDPE) and ethylene vinyl acetate (EVA) blends were
investigated by tensile properties and swelling behavior. The use of CL-MAH improved the
compatibility of RHDPE80/EVA20 blend composition, and tensile properties of the resultant blend
compared well with those of RHDPE/EVA blends. Addition of PE-g-MAH improved the tensile
properties of RHDPE/EVA/PE-g-MAH blends than RHDPE/EVA blends without compatibilizer. The
scanning electron microscopy (SEM) morphologies of fracture surface for RHDPE/EVA blends with
presence of compatibilizers showing better incorporation of two different phases of polymer matrix.
A simple, ready-to-use concentrated specimen smear microscopy method employing a nanometer silicon polyvinylidene fluoride (PVDF) polymer membrane sandwich filtration vessel to concentrate acid-fast bacilli (AFB) in samples (SFV-CSSM, Hunan-Tech New Medical System Co. Ltd. China) was compared with direct sputum smear microscopy (DSSM) to determine its performance using culture on modified Ogawa agar as reference. The results for 4114 clinical samples collected from health facilities in Sabah were interpreted with reference to culture results, sample collection-transportation conditions and clinical data including responses to anti-TB drug treatment. The SFV-CSSM showed higher sensitivity than DSSM (79.4% versus 60.5%) and less background interference. Its ability to detect low levels of AFB at an affordable cost makes it an excellent tool for the screening of pauci-bacillary samples as well as for active case finding in TB control programs.
Frequent detection of sulfonamides (SAs) pharmaceuticals in wastewater has necessitated the discovery of suitable technology for their sustainable remediation. Adsorption has been widely investigated due to its effectiveness, simplicity, and availability of various adsorbent materials from natural and artificial sources. This review highlighted the potentials of carbon-based adsorbents derived from agricultural wastes such as lignocellulose, biochar, activated carbon, carbon nanotubes graphene materials as well as organic polymers such as chitosan, molecularly imprinted polymers, metal, and covalent frameworks for SAs removal from wastewater. The promising features of these materials including higher porosity, rich carbon-content, robustness, good stability as well as ease of modification have been emphasized. Thus, the materials have demonstrated excellent performance towards the SAs removal, attributed to their porous nature that provided sufficient active sites for the adsorption of SAs molecules. The modification of physico-chemical features of the materials have been discussed as efficient means for enhancing their adsorption and reusable performance. The article also proposed various interactive mechanisms for the SAs adsorption. Lastly, the prospects and challenges have been highlighted to expand the knowledge gap on the application of the materials for the sustainable removal of the SAs.
Acanthamoeba castellanii are opportunistic pathogens known to cause infection of the central nervous system termed: granulomatous amoebic encephalitis, that mostly effects immunocompromised individuals, and a sight threatening keratitis, known as Acanthamoeba keratitis, which mostly affects contact lens wearers. The current treatment available is problematic, and is toxic. Herein, an amphiphilic star polymer with AB2 miktoarms [A = hydrophobic poly(ℇ-Caprolacton) and B = hydrophilic poly (ethylene glycol)] was synthesized by ring opening polymerization and CuI catalyzed azide-alkyne cycloaddition. Characterization by 1H and 13C NMR spectroscopy, size-exclusion chromatography and fluorescence spectroscopy was accomplished. The hydrophobic drug itraconazole (ITZ) was incorporated in self-assembled micellar structure of AB2 miktoarms through co-solvent evaporation. The properties of ITZ loaded (ITZ-PCL-PEG2) and blank micelles (PCL-PEG2) were investigated through zeta sizer, scanning electron microscopy and Fourier-transform infrared spectroscopy. Itraconazole alone (ITZ), polymer (DPB-PCL), empty polymeric micelles (PCL-PEG2) alone, and itraconazole loaded in polymeric micelles (ITZ-PCL-PEG2) were tested for anti-amoebic potential against Acanthamoeba, and the cytotoxicity on human cells were determined. The polymer was able to self-assemble in aqueous conditions and exhibited low value for critical micelle concentration (CMC) 0.05-0.06 µg/mL. The maximum entrapment efficiency of ITZ was 68%. Of note, ITZ, DPB, PCL-PEG2 and ITZ-PCL-PEG2 inhibited amoebae trophozoites by 37.34%, 36.30%, 35.77%, and 68.24%, respectively, as compared to controls. Moreover, ITZ-PCL-PEG2 revealed limited cytotoxicity against human keratinocyte cells. These results are indicative that ITZ-PCL-PEG2 micelle show significantly better anti-amoebic effects as compared to ITZ alone and thus should be investigated further in vivo to determine its clinical potential.
The most common material used for blood bags is PVC, which requires the addition of DEHP to increase its flexibility. DEHP is known to cross the polymer barrier and move into the stored blood and, ultimately, the patient's bloodstream. In this work, an alternative prototype composed of SEBS/PP was fabricated through blow-moulding and compared with the commercially available PVC-based blood bag which was designated as the control. The blow-moulded sample layers were welded together using CO2 lasers and optimized to obtain complete sealing of the sides. The samples' performance characteristics were analyzed using water permeability, oxygen permeability, shelf-life, and bioburden tests. The SEBS/PP sample exhibited the highest oxygen permeability rate of 1486.6 cc/m2/24 h after 40 days of ageing, indicating that the sample is conducive for red blood cell (RBC) respiration. On the other hand, the SEBS/PP sample showcased a lower water permeability rate of 0.098 g/h m2 after 40 days of aging, indicating a high-water barrier property and thus preventing water loss during storage. In comparison, the oxygen and water permeability rates of PVC-DEHP were found to be distinctly lower in performance (662.7 cc/m2/24 h and 0.221 g/h m2, respectively). In addition, shelf-life analyses revealed that after 40 days of ageing, polymer samples exhibited no visual damage or degradation. The optimal parameters to obtain adequate welding of the SEBS/PP were determined to be power of 60% (18 W), speed of 70 in/sec and 500 Pulse Per Inch (PPI). Furthermore, the bioburden estimates of SEBS/PP of 115 CFU are markedly lower compared to the bioburden estimate of PVC-DEHP of 213 CFU. The SEBS/PP prototype can potentially be an effective alternative to PVC-based blood bags, particularly for high-risk patients in order to reduce the likelihood of medical issues.
Plastics have become an integral part of human life. Single-use plastics (SUPs) are disposable plastics designed to be used once then promptly discarded or recycled. This SUPs range from packaging and takeaway containers to disposable razors and hotel toiletries. Synthetic plastics, which are made of non-renewable petroleum and natural gas resources, require decades to perpetually disintegrate in nature thus contribute to plastic pollution worldwide, especially in marine environments. In response to these problems, bioplastics or bio-based and biodegradable polymers from renewable sources has been considered as an alternative. Understanding the mechanisms behind the degradation of conventional SUPs and biodegradability of their greener counterpart, bioplastics, is crucial for appropriate material selection in the future. This review aims to provide insights into the degradation or disintegration of conventional single-use plastics and the biodegradability of the different types of greener-counterparts, bioplastics, their mechanisms, and conditions. This review highlights on the biodegradation in the environments including composting systems. Here, the various types of alternative biodegradable polymers, such as bacterially biosynthesised bioplastics, natural fibre-reinforced plastics, starch-, cellulose-, lignin-, and soy-based polymers were explored. Review of past literature revealed that although bioplastics are relatively eco-friendly, their natural compositions and properties are inconsistent. Furthermore, the global plastic market for biodegradable plastics remains relatively small and require further research and commercialization efforts, especially considering the urgency of plastic and microplastic pollution as currently critical global issue. Biodegradable plastics have potential to replace conventional plastics as they show biodegradation ability under real environments, and thus intensive research on the various biodegradable plastics is needed to inform stakeholders and policy makers on the appropriate response to the gradually emerging biodegradable plastics.
Composite materials used in the prosthetic and orthotic fields have helped improve the fabrication of sockets. Laminated sockets proved to be stronger than conventional thermoplastic sockets. The internal surface of a laminated socket plays an important role in patient comfort and is influenced by the material used to fabricate the socket. This study analyzes the internal surface profile of five different materials, that is, Dacron felt, fiberglass, Perlon stockinette, polyester stockinette, and elastic stockinette. All sockets were fabricated using an acrylic resin mix with hardener powder at a ratio of 100:3. The internal surface of the sockets was tested using the Mitutoyo SurfTest SJ-210 series for 20 trials. The overall Ra values were 2.318, 2.380, 2.682, 2.722, and 3.750 µm for fiberglass, polyester, Perlon, elastic stockinette, and Dacron felt. Dacron felt yielded the lowest Ra value, thus, producing the smoothest internal surface but requiring high skill and the correct technique during the fabrication of a laminated socket. Fiberglass is considered the best material for the internal surface despite not producing the lowest value individually but overall is the lowest and most consistent, indicating that it is easy to use to laminate prosthetic sockets.
Nowadays, nano-platforms designed for drug delivery systems (DDSs) such as polymers, liposomes, and micelles have been demonstrated to be clinically efficient. The sustained drug release is one of the advantages of DDSs, especially polymer-based nanoparticles. The formulation could enhance the drug's durability, in which the biodegradable polymers are the most interesting building blocks of DDSs. Nano-carriers could circumvent many issues by localized drug delivery and release via certain internalization routes such as intracellular endocytosis paths and increasing biocompatibility. Polymeric nanoparticles and their nanocomposite are one of the most important classes of materials that can be used for the assembly of nanocarriers that can form complex, conjugated and encapsulated forms. The site-specific drug delivery may arise from the ability of nanocarriers to pass through the biological barrier, their specific interactions with receptors, and passive targeting. The better circulation, uptake, and stability along with targeting attributes lead to lesser side effects and damage to normal cells. Hence, in this review, the most recent achievements on polycaprolactone-based or -modified nanoparticles in drug delivery systems (DDSs) for 5-fluorouracil (5-FU) are presented.
The continuous deterioration of the environment due to extensive industrialization and urbanization has raised the requirement to devise high-performance environmental remediation technologies. Membrane technologies, primarily based on conventional polymers, are the most commercialized air, water, solid, and radiation-based environmental remediation strategies. Low stability at high temperatures, swelling in organic contaminants, and poor selectivity are the fundamental issues associated with polymeric membranes restricting their scalable viability. Polymer-metal-carbides and nitrides (MXenes) hybrid membranes possess remarkable physicochemical attributes, including strong mechanical endurance, high mechanical flexibility, superior adsorptive behavior, and selective permeability, due to multi-interactions between polymers and MXene's surface functionalities. This review articulates the state-of-the-art MXene-polymer hybrid membranes, emphasizing its fabrication routes, enhanced physicochemical properties, and improved adsorptive behavior. It comprehensively summarizes the utilization of MXene-polymer hybrid membranes for environmental remediation applications, including water purification, desalination, ion-separation, gas separation and detection, containment adsorption, and electromagnetic and nuclear radiation shielding. Furthermore, the review highlights the associated bottlenecks of MXene-Polymer hybrid-membranes and its possible alternate solutions to meet industrial requirements. Discussed are opportunities and prospects related to MXene-polymer membrane to devise intelligent and next-generation environmental remediation strategies with the integration of modern age technologies of internet-of-things, artificial intelligence, machine-learning, 5G-communication and cloud-computing are elucidated.
The purpose of this study was to systematically review the impact of nanofillers on the physicomechanical properties of resin-based pit and fissure sealants (RBS). This review included in vitro studies with full-length English-language articles reporting on the physicomechanical properties of nanofilled RBS until February 2023. PubMed, Web of Sciences, Scopus, and LILACS databases were accessed for literature searches. The review was formulated based on the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines and used the Consolidated Standards of Reporting Trials (CONSORT) guidelines and risk of bias Cochrane tool for quality assessment. The search resulted in 539 papers, of which 22 were eligible to be included in the review. Inorganic, polymeric, core-shell, and composite nanomaterials were used to reinforce the studied RBS. The inherent nature of the nanomaterial used, its morphology, concentration, and volume used were the primary parameters that determined the nanomaterial's success as a filler in RBS. These parameters also influenced their interaction with the resin matrix, which influenced the final physicomechanical properties of RBS. The use of nanofillers that were non-agglomerated and well dispersed in the resin matrix enhanced the physicomechanical properties of RBS.
INTRODUCTION: The maxillomandibular relationship (MMR) record is a critical step to establish the new occlusion in implant supported complete mouth rehabilitation. Using patients existing denture for recording the MMR requires implant definitive cast to be modified extensively to completely seat the denture (with unaltered flanges) on it. This may influence the correct seating of the denture on the implant definitive cast causing faulty recording of the MMR.
MATERIALS AND METHOD: Elastomeric record bases, reinforced with the resin framework, are fabricated and relined with the light body elastomeric material when all the healing abutments are in place. The MMR is recorded with these elastomeric record bases using vacuum formed facial surface index of the occluded existing dentures as a guideline.
RESULTS: The elastomeric record bases with facial surface index of the existing dentures can allow clinicians to record MMR records without removing the healing abutments from the mouth with acceptable accuracy. This can save chair-side time of the procedure. The record of facial surfaces of existing complete denture in the form of vacuum formed sheet helps to set the occlusal vertical dimension.
CONCLUSION: Use of facial surface index together with the elastomeric record bases can be the useful alternative technique to record the MMR in patients with implant supported full mouth rehabilitation. Further study is required to prove its routine clinical utility.
KEYWORDS: Implant restorations; maxillomandibular relation; occlusion rim; record base
Microneedle (MN) delivery devices are more accepted by people than regular traditional needle injections (e.g. vaccination) due to their simplicity and adaptability. Thus, patients of chronic diseases like diabetes look for alternative pain-free treatment regimens circumventing regular subcutaneous injections. Insulin microneedles (INS-MNs) are a thoughtfully researched topic (1) to overcome needle phobia in patients, (2) for controlled delivery of the peptide, (3) decreasing the frequency of drug administration, (4) to ease the drug administration procedure, and (5) thus increasing patient adherence to the treatment dosage regimes. MNs physically disrupt the hard outer skin layer to create minuscule pores for insulin (INS) to pass through the dermal capillaries into the systemic circulation. Biodegradable polymeric MNs are of greater significance for INS and vaccine delivery than silicon, metal, glass, or non-biodegradable polymeric MNs due to their ease of fabrication, mass production, cost-effectiveness, and bioerodability. In recent years, INS-MNs have been researched to deliver INS through the transdermal implants, buccal mucosa, stomach wall, intestinal mucosal layers, and colonic mucosa apart from the usual transdermal delivery. This review focuses on the design characteristics and the applications of biodegradable/dissolvable polymeric INS-MNs in transdermal, intra-oral, gastrointestinal (GI), and implantable delivery. The prospective approaches to formulate safe, controlled-release INS-MNs were highlighted. Biodegradable/dissolvable polymers, their significance, their impact on MN morphology, and INS release characteristics were outlined. The developments in biodegradable polymeric INS-MN technology were briefly discussed. Bio-erodible polymer selection, MN fabrication and evaluation factors, and other design aspects were elaborated.
The carbon dioxide (CO2) separation technology has become a focus recently, and a developed example is the membrane technology. It is an alternative form of enhanced gas separation performance above the Robeson upper bound line resulting in the idea of mixed matrix membranes (MMMs). With attention given to membrane technologies, the MMMs were fabricated to have the most desirable gas separation performance. In this work, blend MMMs were synthesised by using two polymers, namely, poly(ether sulfone) (PES) and poly (ethylene glycol) (PEG). These polymers were dissolved in blend N-methyl-2-pyrrolidone (NMP) and dimethylformamide (DMF) solvents with the functionalised multi-walled carbon nanotubes (MWCNTs-F) fillers by using the mixing solution method. The embedding of the pristine MWCNTs and MWCNTs-F within the new synthesised MMM was then studied towards CO2/N2 separation. In addition, the optimisation of the loading of MWCNTs-F for blend MMM for CO2/N2 separation was also studied. The experimental results showed that the functionalised MWCNTs (MWCNTs-F) were a better choice at enhancing gas separation compared to the pristine MWCNTs (MWCNTs-P). Additionally, the effects of MWCNTs-F at loadings 0.01 to 0.05% were studied along with the polymer compositions for PES:PEG of 10:20, 20:20 and 30:10. Both these parameters of study affect the manner of gas separation performance in the blend MMMs. Overall, the best performing membrane showed a selectivity value of 1.01 + 0.05 for a blend MMM (MMM-0.03F) fabricated with 20 wt% of PES, 20 wt% of PEG and 0.03 wt% of MWCNTs-F. The MMM-0.03F was able to withstand a pressure of 2 bar, illustrating its mechanical strength and ability to be used in the post combustion carbon capture application industries where the flue gas pressure is at 1.01 bar.
A halophilic bacterium isolated from mangrove soil sample in Northern Vietnam, Yangia sp. ND199 was found capable of producing homopolymer poly(3-hydroxybutyrate) [P(3HB)], copolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)], and copolymer poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)] from different carbon sources. The presence of 3HB, 3HV, and 4HB monomers were confirmed by gas chromatography and nuclear magnetic resonance analysis. Only P(3HB) was produced using carbon sources such as fructose or by a combination of fructose with 1,5-pentanediol, 1,6-hexanediol, sodium hexanoate, or sodium octanoate. The biosynthesis of P(3HB-co-3HV) was achieved by adding cosubstrates such as sodium valerate and sodium heptanoate. When 1,4-butanediol, γ-butyrolactone or sodium 4-hydroxybutyrate was added to the culture medium, P(3HB-co-4HB) containing 4.0-7.1mol% 4HB fraction was accumulated. The molecular weights and thermal properties of polyesters were determined by gel permeation chromatography and differential scanning calorimeter, respectively. The results showed that Yangia sp. ND199 is able to produce polyester with high weight average molecular weight ranging from 1.3×10(6) to 2.2×10(6) Dalton and number average molecular weight ranging from 4.2×10(5) to 6.9×10(5) Dalton. The molecular weights, glass transition temperature as well as melting temperature of homopolymer P(3HB) are higher than those of copolymer P(3HB-co-3HV) or P(3HB-co-4HB).
Gel polymer electrolytes (GPEs) are developed using poly(1-vinylpyrrolidone-co-vinyl acetate) [P(VP-co-VAc)] as the host polymer, lithium bis(trifluoromethane) sulfonimide [LiTFSI] as the lithium salt and ionic liquid, and 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide [EMImTFSI] by using solution casting technique. The effect of ionic liquid on ionic conductivity is studied and the optimum ionic conductivity at room temperature is found to be 2.14 × 10(-6) S cm(-1) for sample containing 25 wt% of EMImTFSI. The temperature dependence of ionic conductivity from 303 K to 353 K exhibits Arrhenius plot behaviour. The thermal stability of the polymer electrolyte system is studied by using thermogravimetric analysis (TGA) while the structural and morphological properties of the polymer electrolyte is studied by using Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction analysis (XRD), respectively.