Hyperbranched Polyester Polyol Research Articles

An A2 + CB2 approach to the synthesis of hyperbranched polyester polyol and application in PU coatings

An A2 + CB2 approach to the synthesis of hyperbranched polyester polyol and application in PU coatings

Advancements in polyurethane coating: Synthesis and characterization of a novel hyper branched polyester polyol

Hyperbranched polyester polyols have emerged as a promising candidate for polyurethane coatings due to their unique structure and properties. In this context, this paper aims to synthesize a new hyperbranched polyester polyol and evaluate its potential as a polyol for polyurethane coating applications. In this study, the synthesis of hyperbranched polyester polyol involves the reaction between a multifunctional alcohol and a multifunctional carboxylic acid or anhydride. It is further modified by incorporating 2-hydroxyethyl methacrylate and styrene. The properties of the polyester polyol were characterized using various analytical techniques, including FTIR, NMR, SEM and TGA. This paper also provides a discussion on the potential applications of the synthesized hyperbranched polyester polyol in several industries such as automotive, aerospace and construction.

A Hyperbranched Polyol Process for Designing and Manufacturing Nontoxic Cobalt Nanocomposite.

A method for the design and synthesis of a metallopolymer composite (CoNP) based on cobalt nanoparticles using the hyperbranched polyol process was developed. It was shown that hyperbranched polyester polyols in a melted state can be both a reducing agent and a stabilizer of metal nanoparticles at the same time. The mechanism of oxidation of hyperbranched polyol was studied using diffuse reflectance IR spectroscopy. The process of oxidation of OH groups in G4-OH started from 90 °C and finished with the oxidation of aldehyde groups. The composition and properties of nanomaterials were determined with FT-IR and UV-Vis spectroscopy, Nanoparticle Tracking Analysis (NTA), thermogravimetric analysis (TG), powder X-ray diffraction (XRD), NMR relaxation, and in vitro biological tests. The cobalt-containing nanocomposite (CoNP) had a high colloidal stability and contained spheroid polymer aggregates with a diameter of 35-50 nm with immobilized cobalt nanoparticles of 5-7 nm. The values of R2 and R1 according to the NMR relaxation method for CoNPs were 6.77 mM·ms-1 × 10-5 and 4.14 mM·ms-1 × 10-5 for, respectively. The ratio R2/R1 = 0.61 defines the cobalt-containing nanocomposite as a T1 contrast agent. The synthesized CoNPs were nonhemotoxic (HC50 > 8 g/mL) multifunctional reagents and exhibited the properties of synthetic modulators of the enzymatic activity of chymosin aspartic proteinase and exhibited antimycotic activity against Aspergillus fumigatus. The results of the study show the unique prospects of the developed two-component method of the hyperbranched polyol process for the creation of colloidal multifunctional metal-polymer nanocomposites for theranostics.

High-temperature synthesis of cobalt nanoparticles in hyperbranched polyester polyol medium

The synthesis of CoNPs cobalt nanoparticles by the method of polyol- process was proposed, which consists in a high-temperature synthesis of polymer-stabilized metal nanoparticles in a matrix of a fourth-generation hyperbranched polyester polyol. Branched polyester polyol acts as both a reducing agent and a stabilizer at the same time. It has been found that the reduction of the precursor CoCl2 with a hyperbranched polyester polyol occurs at 210°C. The introduction of NaOH into the reaction mixture makes it possible to lower the synthesis temperature by 50°C and leads to a change in the mechanism of in situ ripening CoNPs from the digestive mechanism to direct Ostwald ripening.

High-Temperature Synthesis of Cobalt Nanoparticles in Hyperbranched Polyester Polyol Medium

High-Temperature Synthesis of Cobalt Nanoparticles in Hyperbranched Polyester Polyol Medium

Effect of the Synthetic Approach on the Formation and Magnetic Properties of Iron-Based Nanophase in Branched Polyester Polyol Matrix

This article shows the success of using the chemical reduction method, the polyol thermolytic process, the sonochemistry method, and the hybrid sonochemistry/polyol process method to design iron-based magnetically active composite nanomaterials in a hyperbranched polyester polyol matrix. Four samples were obtained and characterized by transmission and scanning electron microscopy, infrared spectroscopy and thermogravimetry. In all cases, the hyperbranched polymer is an excellent stabilizer of the iron and iron oxides nanophase. In addition, during the thermolytic process and hybrid method, the branched polyol exhibits the properties of a good reducing agent. The use of various approaches to the synthesis of iron nanoparticles in a branched polyester polyol matrix makes it possible to control the composition, geometry, dispersity, and size of the iron-based nanophase and to create new promising materials with colloidal stability, low hemolytic activity, and good magnetic properties. The NMR relaxation method proved the possibility of using the obtained composites as tomographic probes.

Aggregation-Induced Emission of Hyperbranched Polyester Polyols

Aggregation-Induced Emission of Hyperbranched Polyester Polyols

Functionalized Hyperbranched Aliphatic Polyester Polyols: Synthesis, Properties and Applications

Functionalized Hyperbranched Aliphatic Polyester Polyols: Synthesis, Properties and Applications

Doxorubicin-Loaded Hybrid Micelles Based on Carboxyl-Terminated Hyperbranched Polyester Polyol

Doxorubicin-Loaded Hybrid Micelles Based on Carboxyl-Terminated Hyperbranched Polyester Polyol

Carbazole-Based Hyperbranched Polyester Polyol: Structural, Rheological, Thermal and Optical Properties

The present study sought to obtain a hyperbranched polyester polyol derivative with fluorescent properties. Initially, a 4-((4-(9H-carbazol-9-yl)benzyl)oxy)-4-oxobut-2-enoic acid (CAV) was synthesized and esterified with a hyperbranched polyester polyol obtained from fourth generation (HBP) to synthesize carbazole-based hyperbranched polyester polyols (HBPCAV). The proportions employed of CAV were 5, 10, 15, and 20 wt% relative to that of HBP. The grafted CAV percentage (PgCAV) increased with the CAV content. The conversion percentages (CP) of the reactions for obtaining HBPCAV were higher than 95% and the hydroxyl values (OHV) were lower than that of HBP. The modification percentage (MP) of the HBP was between 9.33 and 27.38%. Using proton nuclear magnetic resonance (1H NMR) and infrared (IR) analyses was evidenced the formation of CAV and HBPCAV. Dynamic light scattering (DLS) analysis showed that HBPCAV exhibited aggregations. The number average molar mass (Mn), viscosity (η), and glass transition temperature (Tg) values of the HBPCAV samples were higher than those of the HBP, and also increased with the PgCAV values. The rheological behaviors of the HBP and HBPCAV samples were mainly Newtonian and shear-thinning, respectively. All HBPCAV exhibited electroluminescent properties.

Static and Dynamic Behavior of Polymer/Graphite Oxide Nanocomposites before and after Thermal Reduction.

Nanocomposites of hyperbranched polymers with graphitic materials are investigated with respect to their structure and thermal properties as well as the dynamics of the polymer probing the effect of the different intercalated or exfoliated structure. Three generations of hyperbranched polyester polyols are mixed with graphite oxide (GO) and the favorable interactions between the polymers and the solid surfaces lead to intercalated structure. The thermal transitions of the confined chains are suppressed, whereas their dynamics show similarities and differences with the dynamics of the neat polymers. The three relaxation processes observed for the neat polymers are observed in the nanohybrids as well, but with different temperature dependencies. Thermal reduction of the graphite oxide in the presence of the polymer to produce reduced graphite oxide (rGO) reveals an increase in the reduction temperature, which is accompanied by decreased thermal stability of the polymer. The de-oxygenation of the graphite oxide leads to the destruction of the intercalated structure and to the dispersion of the rGO layers within the polymeric matrix because of the modification of the interactions between the polymer chains and the surfaces. A significant increase in the conductivity of the resulting nanocomposites, in comparison to both the polymers and the intercalated nanohybrids, indicates the formation of a percolated rGO network.

Uncovering the relationship between the structure and acid-base properties for hyperbranched polyester-polyols self-assembled on carbon surfaces

Abstract The self-assembly of three different generations of hyperbranched polyester-polyol polymers, based on 2,2-bis(methylol)propionic acid units (H20, H30, and H40 Boltorn®), on carbon electrodes was studied. The physico-chemical properties of this family of polymers confined on a surface were explored by electrochemical impedance spectroscopy (EIS) and atomic force microscopy (AFM). Surface pKa of the hyperbranched polymer layers were determined by impedimetric titration by EIS based on the variation in the charge transfer resistance of the electroactive redox probe [Fe(CN)6]4−/[Fe(CN)6]3− at different pH. AFM was used to characterize the surface topography and also its viscoelastic properties by the acquisition of phase images. The relation between structure and acid-base properties can be explained in terms of a rearrangement of the layer due to the effect of intermolecular hydrogen bonds and adsorbate-substrate interactions. In this study, we report a powerful, versatile and yet simple procedure for functionalizing carbon materials surfaces without pre-treatment requirements, which could be useful to generate promising platforms for the development of sensors and drug delivery systems.

Study of coating performance of bio-based hyperbranched polyester polyol/graphene oxide composites in PU-coating

The present work reports, two types of bio-based hyperbranched polyester polyols (HyBPs) were synthesized from castor oil-based polyols (monoglyceride and fatty amide) and 2,2-bis(hydroxymethyl) propionic acid. The structure of HyBPs was determined by FTIR and NMR. Graphene oxide was prepared from graphene powder by the Hummer’s method and characterized by XRD and FESEM. Further, the composites of HyBPs and graphene oxide nanoparticles in various weight percentages (0, 0.1 and 0.5% of graphene oxide with respect to HyBPs weight) together with isophorone diisocyanate (maintaining an OH:NCO ratio of 1:1.2) were prepared. The coating properties like crosscut adhesion, impact, gloss and scratch resistance of HyBPs polyurethane graphene oxide nanocomposite coatings were studied. The chemical resistance of coatings was determined by immersion test in 0.5 N NaOH, 0.5 N HCl, 3.5% NaCl, water and xylene. Surface morphology, thermal stability and electrochemical properties of the coatings were recorded by FESEM, TGA and potentiostat, respectively.

Properties of the thermoplastic starch/polylactic acid blends compatibilized by hyperbranched polyester

With the aim of to contribute to the employ of new compatibilizing agent and to the preparation of biodegradable materials, in this study were obtained thermoplastic starch/polylactic acid blends and was evaluated the compatibilizing effect of a hyperbranched polyester polyol of second generation modified with polylactic acid in these blends. The blends were prepared in a torque rheometer. In all cases the weight ratio of thermoplastic starch/polylactic acid was 50/50 wt%. The proportions of the compatibility were 5 wt%, 10 wt% 15 wt%, and 20 wt% regard to the total amount of thermoplastic starch and polylactic acid. The blends were characterized by infrared, thermogravimetric, differential scanning calorimetry, X-ray diffraction, scanning electron microscopy and rheological analyses. Torque value decreased with the proportion of compatibilizing. Therefore, the compatibilizing also acted as plasticizing. By infrared analysis was observed that the increasing on the compatibilizing content enhanced the intensity of the signals corresponding to OH and C=O groups. By X-ray diffraction and differential scanning calorimetry analyses was observed a reduction of the crystallinity of the blends obtained with compatibilizing. By rheological analysis was evidenced the formation of a microstructure, which is able to elastically deform.

Evaluation of the rheological properties in solution and molten state of hyperbranched polyester polyols obtained of first and second generation

The hyperbranched polyesters have gain great attention since these materials have smallest hydrodynamic dimensions, high functionality, good solubility and they may be modified for obtaining compounds for specific applications. There are few reports about the rheological properties on the solution and molten state of the hyperbranched polyesters polyols obtained of the first and second generation, especially those prepared from dimethyl propionic acid and pentaerythritol. Thus, the aim of this study is to evaluate the rheological properties in solution and molten state of these materials. Furthermore, the hydrodynamic dimensions by dynamic light scattering by using dimethyl formamide and dimethyl sulfoxide as solvents also were analyzed. The hydrodynamic dimensions on volume of the hyperbranched polyesters polyols obtained of second generation by using dimethyl formamide as solvent were greater than those of first generation, but the behavior was different when was used dimethyl sulfoxide as solvent. Furthermore, these materials exhibited aggregations. The rheological behavior in solution showed that all samples exhibited lowest viscosity and a Newtonian region between 1 and 60 s−1, then this behavior changed to shear thickening. By rheological analysis in molten state was evidenced a shear-thinning behavior to these materials.

Evaluation of a hyperbranched polyester polyol as plasticizing agent for composites of recycled polystyrene and rice husk

This study makes a contribution to the preparation of composites from recycled polystyrene and rice husk (it is mainly incinerated producing environmental contamination in Norte de Santander department-Colombia), which will contribute to reduce the accumulation of waste derivatives from polymeric and rice industries in this region. Hence, the aim of this work was to use a hyperbranched polyester as plasticizing agent and to evaluate its influence on the properties of the composites. The proportions of the recycled polystyrene and rice husk were 60 wt% and 40 wt% respectively. In the case of the polyester, were employed amount of 10 wt%, 20 wt%, 30 wt% and 40 wt%. Also was prepared a control sample (0 % of polyester). The results of infrared analysis evidenced changes in the absorption of the hydroxy groups. The thermogravimetric analysis showed that the first thermal decomposition of the composites decreased with the polyester content, but it did not follow the same trend on mechanical properties. The results of scanning electronic microscopy analysis allowed evidence that the fracture mechanism of the composite was fragile. The viscosity of the control sample was lower than that of the composites obtained with the polyester.

Synthesis of New Hyperbranched Dendrimers with Terminal Cationic Groups Based on Boltorn H20 Polyester Polyol

Terminal polychlorides of hyperbranched polyester polyol Boltorn H20 were synthesized. Subsequent treatment of the resultant polychlorides with absolute pyridine or triphenylphosphine led to the formation of products of varying degrees of functionalization, containing pyridinium or triphenylphosphonium moieties in terminal positions.

Compatibilization of LDPE/PA6 by Using a LDPE Functionalized with a Maleinized Hyperbranched Polyester Polyol

Low density polyethylene (LDPE)/polyamide6 (PA) blends can lead to a synergy between the properties of these materials. These blends are employed mainly in the packing industry, especially in food factories. The problem of this system is that it is inmiscible, hence requires to be compatibilized. The aim of this study is to compatibilize blends of LDPE/PA6 using a LDPE modified with a maleinized hyperbranched polyol polyester (LDPE-g-MHBP) as a compatibilizing agent. Therefore blends of LDPE (50 wt%)/PA (50 wt%) were prepared by using proportions of 5 (Blend5), 10 (Blend10), 15 (Blend15) and 20 (Blend20) wt% of the LDPE-g-MHBP of the total mix. On the other hand, to determine the efficiency of the LDPE-g-MHBP as a compatibilizing agent, a Blend0 (blends of LDPE (50 wt%)/PA (50 wt%) without LDPE-g-MHBP) was used as the control sample. By infrared (IR) analysis was evidenced the interactions between PA and LDPE-g-MHBP. By differential scanning calorimetry analysis (DSC) was observed that the LDPE-g-MHBP increased the crystallinity of the LDPE phase, but the behavior was opposite to PA. The thermal stability and the viscosity of the blends obtained with LDPE-g-MHBP were higher than those of the Blend0. Scanning electron microscopy (SEM) analysis revealed that the LDPE-g-MHBP ostensibly improved the miscibility of the LDPE/PA blends.

Evaluation of the effect of a hyperbranched polyester on the thermal, rheological, morphological and mechanical properties of polyvinyl chloride/hemp fiber blends

The aim of this study was to investigate the effect of the hyperbranched polyester polyol from second generation content on the structural, thermal, rheological, morphological and mechanical properties of recycled polyvinyl chloride/hemp fiber/hyperbranched polyester polyol obtained from second generation blends. In all blends, the amounts of recycled polyvinyl chloride and hemp fiber were 70 wt% and 30 wt% respectively. The blends were obtained in a torque rheometer. The proportions of hyperbranched polyester polyol regards to those of the polyvinyl chloride and hemp fibers were 5 wt%, 10 wt%, 15 wt% and 20 wt%. Additionally, a recycled polyvinyl chloride/hemp fiber blend was prepared to be used as control blend. Infrared analysis was then used to evidence the interaction between components of the blends. The thermal stability of the recycled polyvinyl chloride/hemp fiber/hyperbranched polyester polyol blends was lower than that of the polyvinyl chloride. Furthermore, it was not observed a trend in the thermal behavior of the recycled polyvinyl chloride blends. Hyperbranched polyester polyol increased the glass transition temperature of the blends. Additionally, rheological analysis results indicated that the hyperbranched polyester polyol reduced the viscosity of the blends.

Maleinized Hyperbranched Polyol Polyester: Effect of the Content of Maleic Anhydride in the Structural, Thermal and Rheological Properties

The aim of this work is to obtain the material that, in the future, may become a better alternative, as a functionalizing agent, to maleic anhydride (MA), or a crosslinking agent with the least amount of functional groups. To achieve that goal, a hyperbranched polyester polyol (HBP) of the second generation (HBP2G) was modified with MA to obtain HBP2GMA. The effects of the proportion of MA in the structural, thermal, and rheological properties of the HBP2GMAs were evaluated. Furthermore, these properties were compared with those of the HBP2G. A reduction in the intensity of peak corresponding to the OH stretching of HBP2G was observed with the increase in the extent of HBP2G modification by the analysis of the infrared (IR). HBP2GMAs showed a peak at 3030 cm-1 in their IR spectra, which was due to the -CH=CH- stretching of MA. This was further assessed by 1H NMR analysis. The number of MA units grafted into HBP2G was between 4 and 9, indicating a high degree of functionality. All materials possessed viscosity values below 34.94 Pa·s at 110 °C, which were dependent on the grade of the modification percentage (MP) and the molar content of MA grafted into HBP2G. Mass spectrometry analysis demonstrated the formation of products by the esterification reaction between the HBP2G and MA. The thermal stability of the HBP2GMAs determined as the decomposition temperature (Td) was between 258 and 281 °C which was better than that of the HBP2G.