Anhydride Polymer Research Articles

Production of Sorbitol via Hydrogenation of Glucose over Ruthenium Coordinated with Amino Styrene-co-maleic Anhydride Polymer Encapsulated on Activated Carbon (Ru/ASMA@AC) Catalyst.

Sorbitol, a product primarily derived from glucose hydrogenation, has extensive applications in the pharmaceutical, chemical and other industries. Amino styrene-co-maleic anhydride polymer encapsulated on activated carbon (Ru/ASMA@AC) catalysts were developed for efficient glucose hydrogenation and were prepared and confined Ru by coordination with styrene-co-maleic anhydride polymer (ASMA). Through single-factor experiments, optimal conditions were determined to be 2.5 wt.% ruthenium loading and a catalyst usage of 1.5 g, 20% glucose solution at 130 °C, reaction pressure of 4.0 MPa, and a stirring speed of 600 rpm for 3 h. These conditions achieved a high glucose conversion rate of 99.68% and a sorbitol selectivity of 93.04%. Reaction kinetics testing proved that the hydrogenation of glucose catalyzed by Ru/ASMA@AC was a first-order reaction, with a reaction activation energy of 73.04 kJ/mol. Furthermore, the catalytic performance of the Ru/ASMA@AC and Ru/AC catalysts for glucose hydrogenation were compared and characterized by various detection methods. The Ru/ASMA@AC catalyst exhibited excellent stability after five cycles, whereas the traditional Ru/AC catalyst suffered from a 10% decrease in sorbitol yield after three cycles. These results suggest that the Ru/ASMA@AC catalyst is a more promising candidate for high-concentration glucose hydrogenation due to its high catalytic performance and superior stability.

A novel epoxy vitrimer with low dielectric constant at high‐frequency

AbstractVitrmers are a new type of functional resins having the majority of published studies focused on reprocessing, recycling, healing, welding, and shape memory, and their mechanical properties are extensively investigated. While most of the intended applications of these vitrimers are related to elastomers and composites, little research has been published on their dielectric properties and their applications in tele‐communication fields. Herein, dielectric property of four typical epoxy‐anhydride vitrimers were investigated. Vitrimer catalyzed by Zn(Acac)2(zinc acetylacetonate) show excellent re‐processability, which were further improved by introducing MTHPA (methyl terahydrophthalic anhydride) and styrene maleic anhydride (SMA) polymers. The modified epoxy vitrimer shows favorable Tgof 106°C and low dielectric constant (2.77 at 10 GHz). Notably, the modified vitrimer are still re‐processable and degradable due to the dynamic ester bonds, and maintains its dielectric and thermal performances after being reprocessed.

One-step fabrication of robust polyvinyl chloride loose nanofiltration membranes by synthesizing a novel polyether amine grafted styrene-maleic anhydride copolymer

Loose nanofiltration membrane possesses obvious advantages for treating textile wastewater to recycle the useful resources. However, the increasingly complicated composition of wastewater has raised significant challenges to the efficient separation of dye/salt mixtures and antifouling properties. Herein, a novel polyether amine grafted styrene-maleic anhydride polymer (SMA-g-PEA) was synthesized and utilized as the additive for fabricating PVC-based loose nanofiltration membranes. Segregated amphiphilic SMA-g-PEA in the membrane formation created uniform macropores on the surface due to its pore-forming ability, and the self-crosslinking and accelerated phase inversion generated a thin nanofiltration separation layer. By adjusting the grafting degree of PEA, the optimized PVC/SMA-g-PEA membrane displayed high rejections of methyl blue (96.4 %), Congo red (93.3 %) and acid fuchsin (68.6 %) and extremely low rejections of NaCl (0.18 %), Na2SO4 (4.75 %) and MgSO4 (2.24 %) due to the combination of size sieving and electrostatic interaction. Importantly, it also exhibited a permeate flux of 210 L/m2·h·bar during filtering the methyl blue/NaCl solution and a dye/salt selectivity of 31.93. Moreover, a strong and stable hydration layer was constructed on the membrane surface by integrating the amphiphilic characteristic of SMA-g-PEA and zwitterion potential in acid environment. Consequently, the antifouling properties were dramatically elevated by “fouling resistant” and “fouling release” strategies.

Study on the low temperature fluidity of biodiesel blended oil by maleic anhydride polymers with different molecular structures

ABSTRACT Adding pour point depressant (PPD) is one of the simple and high-efficiency methods to solve poor low-temperature flow performance of biodiesel-diesel blends, but the enhancing effect of polymeric PPDs is always influenced by the molecular structure. To explore the molecular structure-activity relationships, in this study, tetradecyl methacrylate-maleic anhydride (C14MC-MA), tetradecyl methacrylate-Itaconic anhydride (C14MC-IA) and tetradecyl methacrylate-citraconic anhydride (C14MC-CA) were synthesized and added into B20 (20 vol.% biodiesel +80 vol.% diesel). The enhancing effects of these different-structured copolymers on the low-temperature fluidity of B20 were compared. Results indicated that the enhancing effects of these copolymers were obviously affected by their molecular structure and polymerization ratios. The polar group imparted by acid anhydrides and the long side-chain alkyl group in methacrylic acid significantly enhanced the depressive effects, resulting in better fluidity at low temperatures for the synthesized polymers. Apart from the aldehyde group identical to that of MA, the methyl and methylene groups in CA and IA have considerable polarity and solubility, leading to an improvement of inhibition. Among that, C14MC-CA showed better enhancing effects on solid point (SP) and cold filter plugging point (CFPP) of B20 than that of C14MC-MA and C14MC-IA. When the dosage of C14MC-CA was 1000 ppm and the mole ratio was 9:1, the best depressive effect was achieved, and CFPP and SP were reduced by 12°C and 14°C, respectively. Also, the depressing mechanism of these copolymers on the eutectic reaction was studied by polarizing microscopy, differential scanning calorimetry and viscosity-temperature curves.

Solvent-free electrospinning of liquid polybutadienes and their in-situ photocuring

A single-step approach to rapidly convert low molecular weight polybutadienes into fine rubber crosslinked fibers and nonwoven mats without using any heat or solvent was described. This environmentally friendly method consisted in the electrospinning at room temperature of liquid polybutadiene and polybutadiene-graft-maleic anhydride polymers without any solvent; the flying jet was irradiated to trigger the in-situ curing of the forming fibers at ambient conditions, obtaining a good control over the fibrous morphology and enhancing the performance of the membranes. The kinetics of the photo-crosslinking reaction was studied through FT-IR spectroscopy. Liquid polybutadiene-graft-maleic anhydride polymers demonstrated a faster rate of photocuring, compared to neat polybutadienes. In order to further speed up the reaction, a thiol-based crosslinker and a photoinitiator were introduced into the formulations. The photo-induced crosslinking was more efficient as different reactions concomitantly took place: besides the thiol-ene crosslinking involving the multifunctional thiol crosslinker, the oxidation of the polybutadiene chains and the esterification of the maleic anhydride moieties occurred. Moreover, a polar additive was used to control the electrospinning process by lowering the viscosity and increasing the electrical conductivity. The structural, thermal and surface properties of the fabricated polybutadiene-based electrospun membranes were assessed. The membranes exhibited an excellent morphology stability, high insolubility, good thermal properties and a pronounced hydrophobic character.

Uptake of methylene blue on divinylbenzene cross-linked chitosan/maleic anhydride polymer by adsorption process

In this work, divinylbenzene selected as the cross-linking agent, a two-step one pot method based on the acylation reaction between maleic anhydride and chitosan had been developed to prepare a series of divinylbenzene cross-linked chitosan/maleic anhydride polymers (CS/MAH-DVB), which were used to remove cationic dye methylene blue (MB) from aqueous solutions. The synthesized polymers were characterized by FT-IR, XPS, SEM, TG and pH-drift methods. The adsorption parameters were discussed including pH, contact time, initial concentration of dye and temperature. The maximum adsorption capacities were 448 mg g −1 , 482 mg g −1 and 503 mg g −1 respectively for three CS/MAH-DVB polymers with different molar ratios at 298 K, which were superior to other reported bio-based adsorbents. The adsorption process was found well to follow pseudo-second-order model and Sips isotherm. The adsorption mechanism was attributed to electrostatic interaction and π-π stacking interaction between MB and CS/MAH-DVB polymers. Furthermore, the CS/MAH-DVB polymers could easily be recycled by washing with acidic acetone, demonstrating excellent stability and favorable recyclability over five cycles. These results indicated the chitosan grafted maleic anhydride and further cross-linking using divinylbenzene could promote the adsorption performance of chitosan. • CS/MAH-DVB polymers were prepared through a facile method. • The adsorption capacity of chitosan was promoted by introducing carboxyl functional groups and chemical crosslinking. • Adsorption mechanism was electrostatic interaction and π-π stacking interaction. • The maximum capacity of CS/MAH-DVB-3 reached 503 mg g −1 .

Optimisation of reaction parameters for a novel polymeric additives as flow improvers of crude oil using response surface methodology

In recent years, polymeric additives have received considerable attention as a wax control approach to enhance the flowability of waxy crude oil. Furthermore, the satisfactory model for predicting maximum yield in free radical polymerisation has been challenging due to the complexity and rigours of classic kinetic models. This study investigated the influence of operating parameters on a novel synthesised polymer used as a wax deposition inhibitor in a crude oil pipeline. Response surface methodology (RSM) was used to develop a polynomial regression model and investigate the effect of reaction temperature, reaction time, and initiator concentration on the polymerisation yield of behenyl acrylate-co-stearyl methacrylate-co-maleic anhydride (BA-co-SMA-co-MA) polymer by using central composite design (CCD) approach. The modelled optimisation conditions were reaction time of 8.1 h, reaction temperature of 102 °C, and initiator concentration of 1.57 wt%, with the corresponding yield of 93.75%. The regression model analysis (ANOVA) detected an R2 value of 0.9696, indicating that the model can clarify 96.96% of the variation in data variation and does not clarify only 3% of the total differences. Three experimental validation runs were carried out using the optimal conditions, and the highest average yield is 93.20%. An error of about 0.55% was observed compared with the expected value. Therefore, the proposed model is reliable and can predict yield response accurately. Furthermore, the regression model is highly significant, indicating a strong agreement between the expected and experimental values of BA-co-SMA-co-MA yield. Consequently, this study’s findings can help provide a robust model for predicting maximum polymerisation yield to reduce the cost and processing time associated with the polymerisation process.

Preparation and characterization of maleic anhydride‐grafted desulfurization rubber powder by free‐radical polymerization

AbstractThe objective of the article was to enhance the recycling value of solid waste rubber by surface functionalization of desulfurized rubber powder using a one‐pot method based on free‐radical polymerization theory. Fourier transform infrared spectroscopy, X‐ray photoelectron spectroscopy, thermogravimetric analysis, scanning electron microscopy, and elemental analysis were used to characterize the maleic anhydride‐grafted desulfurized rubber powder, and the grafting mechanism was also investigated. Fourier transform infrared spectroscopy and X‐ray photoelectron spectroscopy confirmed that maleic anhydride was grafted onto the desulfurized rubber powder. Thermogravimetric analysis indicated that the maleic anhydride‐grafted desulfurized rubber powder and desulfurized rubber powder possessed different thermal properties and structure. The results of scanning electron microscopy and elemental analysis illustrated that the surface of the desulfurized rubber powder was covered with a layer of fold‐like maleic anhydride polymer. The mechanism of grafting desulfurized rubber powder with maleic anhydride may be achieved by replacing the active α‐H on the methylene group of the desulfurized rubber macromolecule chain.

Synthesis, Optical, Thermal and Structural Characteristics of Novel Thermocleavable Polymers Based on Phthalate Esters.

In this work three novel phthalate-based thermocleavable copolymers, PBTP-11, PBTDTP-11 and PFDTP-11 have been designed and synthesized. PBTP-11 and PBTDTP-11 were prepared by copolymerizing distannylated bithiophene without or with flanked thienyl groups as the electron-donor units with dibrominated secondary phthalate ester as the electron-acceptor units. PFDTP-11 was prepared by copolymerizing distannylated fluorene flanked by thienyl groups as the electron-donor moieties with dibrominated secondary phthalate ester as the electron-acceptor moieties. All polymers were prepared via the Stille polymerization. The impact of two different electron-donor units on the solubility, molecular weights, optical properties, thermal and structural properties of the resulting polymers were investigated. PFDTP-11 had the highest average molecular weight (Mn = 16,400 g mol−1). The polymers had Eg in the range of 2.11–2.58 eV. After thermal treatment, the Eg of the polymers were reduced by around 0.3–0.4 eV. This significant control over bandgap is promising and opens a gate towards commercializing these copolymers in energy harvesting devices such as solar cells. TGA data showed weight loss at around 300 °C, corresponding to the elimination of the secondary ester groups. After annealing, the soluble precursor polymers were transformed into active phthalic anhydride polymers and the resulting films were completely insoluble in all solvents, which shows good stability. Powder XRD studies showed that all polymers have an amorphous nature in the solid state, and therefore can be employed as electrolytes in energy devices.

Preparation and characterization of acrylic resin encapsulated n-dodecanol microcapsule phase change material

Nontoxic, low-cost microcapsule phase change materials (MicroPCMs) were successfully manufactured via suspension polymerization, in which n-dodecanol was employed as the core material and crosslinked polymethyl methacrylate as the wall material. Alkylphenol polyoxyethylene ether (OP-10), polysorbate-20 (Tween-20), sodium salt of styrene-maleic anhydride polymer (SMA), sodium dodecyl sulfonate (SDS), and hexadecyltrimethylammonium chloride (1631) were employed as emulsifiers to investigate the effects of the type and amount of emulsifier on MicroPCMs. In addition, the effects of different types of crosslinking agents on the fabrication of MicroPCMs were investigated. Scanning electron microscopy was used to observe the micro-morphology of MicroPCMs. The chemical structure of the MicroPCMs was detected via Fourier transform infrared spectroscopy. The thermal properties and thermal stability of the MicroPCMs were analyzed using a differential scanning calorimeter and a thermal gravimetric analyzer, respectively. Particle size distributions of the MicroPCMs were measured using a particle size analyzer. The results demonstrate that MicroPCMs with regular morphology were prepared when the mass ratio of the SMA to the oil phase was 3%, and the latent heat and yield of the MicroPCMs were 80.29 J g−1 and 84%, respectively. Furthermore, the MicroPCMs were successfully synthesized using pentaerythritol triacrylate containing the hydroxyl group as the crosslinking agent with an average particle size of 14.18 μm and excellent thermal stability.

Synthesis, Modification, and Application of Sulfonated Poly(styrene-co-maleic anhydride) as a Stain Blocker for Polyamides: Polymer Chemistry for the Undergraduate Organic Laboratory

A laboratory exercise for the synthesis of a sulfonated styrene-co-maleic anhydride polymer and its application as a stain blocker on nylon-6,10, is described. The effectiveness of the sulfonated polymer to prevent the conjugate base of an acid dye from staining the polyamide is demonstrated. This experiment is designed for second-semester, second-year undergraduate organic chemistry students. Specifically, this laboratory experiment focuses on providing experience with radical chain and step-growth polymerizations, interfacial reactions, electrophilic aromatic substitution (sulfonation), and the importance of intermolecular forces.

Maleic Anhydride Cross-Linked β-Cyclodextrin-Conjugated Magnetic Nanoadsorbent: An Ecofriendly Approach for Simultaneous Adsorption of Hydrophilic and Hydrophobic Dyes.

A magnetic nanoadsorbent with a cross-linked β-Cyclodextrin maleic anhydride polymer capable of simultaneous removal of hydrophilic and hydrophobic dyes was developed with high efficacy and desorption/recycling efficiency. The effect of various parameters (concentration, adsorbent dosage, contact time, pH, and temperature) was evaluated to assess the optimum adsorption conditions. The superparamagnetic nanoadsorbent (SPNA) could be easily separated by magnetic decantation and showed maximum removal of malachite green with 97.2% adsorption efficiency. Studies on simultaneous adsorption of dyes from a mixture were performed and the adsorption capacity was calculated. Interestingly, the phenomenon of competitive adsorption was observed. The adsorption process can be fitted well into the Langmuir isotherm model and follows pseudo-second-order kinetics. SPNA could be effectively regenerated and recycled at least five times without any significant loss in removal efficiency. SPNA could be an ideal adsorbent for water remediation because of excellent dye removal efficiency in addition to chemical stability, ease of synthesis, and better reusability.

Fast removal of methylene blue (MB) with functionalized resin

Herein, a new adsorbent was developed in order to fast and effective removal of MB from aqueous solution. For this, crosslinked maleic anhydride polymer was synthesized by copolymerization of maleic anydride (MA) with divinyl benzene (DVB) in DMF at 75 °C using a radical initiator AIBN. A new functionalized resin containing carboxylic acid groups was prepared with modification of crosslinked maleic anydride resin with 5-aminoisophthalic acid. Prepared resin was characterized with FTIR, TGA/DTA and SEM. Parameters affecting adsorption such as pH, initial dye concentration and adsorption time, and also, different isotherm and kinetic models were studied. It was observed that synthesized resin could be used to MB fast removal wide pH and concentration range very high efficiency. It was also found to be that Freundlich isotherm model (R2 = 0.9993) and second order kinetic models are much more suitable for adsorption of MB. Moreover, it was also observed that synthesized resin could be used at least five times without losing its original activity.

Room temperature phosphorescence of 4-bromo-1,8-naphthalic anhydride derivative-based polyacrylamide copolymer with photo-stimulated responsiveness

Room temperature phosphorescence emission was achieved by host–guest recognition between γ-cyclodextrin and a 4-bromo-1,8-naphthalic anhydride polymer, which can be controlled by the photo-isomerization of the azobenzene unit of the other polymer.

Preparation, characterization, and antibacterial activity of NiFe2O4/PAMA/Ag–TiO2 nanocomposite

We have described a facile fabrication of silver deposited on the TiO2, Poly Acrylonitrile Co Maleic Anhydride (PAMA) polymer and nickel ferrite composite (NiFe2O4/PAMA/Ag–TiO2) through a three-step procedure. A pre-synthesized NiFe2O4 was first coated with PAMA polymer and then Ag–TiO2 was deposited on the surface of PAMA polymer shell. After the characterization of this three-component composite by various techniques, such as FTIR, XRD, FESEM, BET, TEM and VSM, it was impregnated in standard antibiotic discs. The antibacterial activity of NiFe2O4/PAMA/Ag–TiO2 nanocomposite was investigated against some gram positive and gram negative bacteria by employing disc diffusion assay and then compared with that of naked NiFe2O4, NiFe2O4/Ag, AgNPs and NiFe2O4/PAMA. The results demonstrated that the AgNPs, when embedded in TiO2 and combined with NiFe2O4/PAMA, became an excellent antibacterial agent. The NiFe2O4/PAMA/Ag–TiO2 nanocomposite could be readily separated from water solution after the disinfection process by applying an external magnetic field.

Influence of Styrene Maleic Anhydride Compatibilizer on the Properties of Polyurethane Carbon Nanocomposites

In this study styrene maleic anhydride polymer was used as compatibilizer in making nanocomposites of polyurethane with carbon nanotubes (single walled) using twin screw extruder. The dispersion of nanotubes in polymer matrix was confirmed using scanning electron microscopy and fourier transform infrared spectroscopy. The thermal properties were analysed using differential scanning calorimetry and thermogravimetric analyser. The tensile strength of the nanocomposites was estimated using Instron tensile testing machine. The result reveals that the addition of compatibilizer increases the tensile strength and the degradation temperature. In addition the energy calculation shows by using the compatibilizer the energy consumption of the extruder can be reduced.

Biocompatibility of polysebacic anhydride microparticles with chondrocytes in engineered cartilage

One of main challenges in developing clinically relevant engineered cartilage is overcoming limited nutrient diffusion due to progressive elaboration of extracellular matrix at the periphery of the construct. Macro-channels have been used to decrease the nutrient path-length; however, the channels become occluded with matrix within weeks in culture, reducing nutrient diffusion. Alternatively, microparticles can be imbedded throughout the scaffold to provide localized nutrient delivery. In this study, we evaluated biocompatibility of polysebacic anhydride (PSA) polymers and the effectiveness of PSA-based microparticles for short-term delivery of nutrients in engineered cartilage. PSA-based microparticles were biocompatible with juvenile bovine chondrocytes for concentrations up to 2mg/mL; however, cytotoxicity was observed at 20mg/mL. Cytotoxicity at high concentrations is likely due to intracellular accumulation of PSA degradation products and resulting lipotoxicity. Cytotoxicity of PSA was partially reversed in the presence of bovine serum albumin. In conclusion, the findings from this study demonstrate concentration-dependent biocompatibility of PSA-based microparticles and potential application as a nutrient delivery vehicle that can be imbedded in scaffolds for tissue engineering.

Investigating the Degradation Behavior of LDPE-grafted Maleic Anhydride for Use as Compatibilizer in Environmentally Degradable Compositions

In this paper, we report the degradation behavior of a LDPE-grafted Maleic anhydride polymer prepared using a reactive extrusion technique. 70 ± 5 µm blown films were exposed to oxidative environments, and the degradation was followed by monitoring physico-chemical and morphological changes. The studies indicated that grafting with Maleic anhydride does not affect the degradation characteristics of the base polymer. Kinetic parameters of degradation, as estimated using non-isothermal TGA, were used to estimate the theoretical lifetime of the polymers, which remained unaltered due to grafting. The results, however, indicated that cobalt stearate, a typical pro-oxidant, led to massive degradation during thermal processing.

Rheokinetic cure characterization of epoxy–anhydride polymer system with shape memory characteristics

An epoxy resin capable of exhibiting shape memory property was derived by curing diglycidyl ether of bisphenol A (DGEBA) with a blend of carboxy telechelic poly(tetramethyleneoxide) (PTAC) and pyromellitic dianhydride (PMDA). The cure kinetics of DGEBA/PTAC/PMDA blend of varying compositions was investigated using isothermal rheological analysis. The overall reaction conformed to a second-order autocatalytic model. The kinetic parameters including reaction order, kinetic constants and activation energy were determined. The results showed that increase of PTAC decreased the overall activation energy and frequency factor of the cure reaction. This effect resulted in a diminution of the overall rate of curing. The catalysis by PTAC has its origin from the activation of epoxy groups by the protons of the COOH groups. The autocatalysis was caused by the COOH groups generated by the reaction of alcohol groups with anhydride. The activation energy for the autocatalysis was more than that for the primary reaction as the COOH groups responsible for autocatalysis were generated on a sterically hindered polymer backbone. The kinetics helped generate a master equation conforming to second-order autocatalytic model that could predict the cure profile of a specified resin system at a given temperature, leading to cure optimization.

Synthesis of functionalized amphiphilic polymers for coating quantum dots

Quantum dots (QDs) need to be attached to other chemical species if they are to be used as biomarkers, therapeutic agents or sensors. These materials also need to disperse well in water and have well-defined functional groups on their surfaces. QDs are most often synthesized in the presence of ligands such as trioctylphosphine oxide, which render the nanoparticle surfaces hydrophobic. We present a complete protocol for the synthesis and water solubilization of hydrophobic CdSe/ZnS QDs using designer amphiphilic polymeric coatings. The method is based on functionalization of an anhydride polymer backbone with nucleophilic agents. Small functional groups, bulky cyclic compounds and polymeric chains can be integrated into the coating prior to solubilization. We describe the preparation of acetylene- and azide-functionalized QDs for 'click' chemistry. The method is universal and applicable to any type of nanoparticle stabilized with hydrophobic ligands able to interact with the alkyl chains in the coating in water.