Colloid and Polymer Science最新文献

In this paper, rigid polybenzenedimethanol ester/terephthalic acid-co-butyl adipate (PBPAT) was prepared introducing rigid 1,4-benzenedimethanol (PXG) monomers into the molecular chain of polybutylene terephthalate (PBAT) via melt polycondensation. The co-polyesters were structurally characterized using Fourier transform infrared spectroscopy (FTIR) and liquid–solid nuclear magnetic resonance (¹H-NMR). Molecular weight, thermal properties, crystallinity, and hydrophilicity were further analyzed using gel permeation chromatography (GPC), X-ray diffractometer (XRD), differential scanning calorimeter (DSC), integrated thermal analyzer (TGA), and contact angle measurements. The mechanical properties of PBPAT were evaluated using a universal tensile testing machine and a rotational rheometer. The results indicated that the molecular weight of PBPAT reached 3.54 × 10⁴ g/mol. The crystallinity increased from 11.57 to 14.07% compared to PBAT. Moreover, the tensile strength enhanced from 17.70 to 25.21 MPa, while the elastic modulus increased from 132.28 to 208.66 MPa compared to PBAT.

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In this paper, a series of novel poly(terephthalic acid-co-caproic acid terephthalate/terephthalic acid-co-caproic acid butylene terephthalate) (PBPAT) with varying PXG contents were prepared via melt polycondensation method using terephthalic acid, adipic acid, 1,4-butanediol, and 1,4-benzenedimethanol as raw materials. The influence of PXG on the mechanical, thermal, and hydrophilic properties of the copolyester was systematically investigated.

Using acrylamide, methyl acryloyloxyethyl trimethyl ammonium chloride, acrylamidomorpholine, and eicosyl dimethyl allyl ammonium chloride as raw materials, herein, a high-temperature- and salt-resistant hydrophobic associative polymer—ADOC—is synthesized via free-radical polymerization in an aqueous solution. The synthesis of ADOC is confirmed via Fourier-transform infrared spectroscopy and proton nuclear magnetic resonance. The involved molecular microaggregation structure is observed through scanning electron microscopy, and associative-network molecular aggregates are formed. The rheological properties of ADOC are determined using a rheometer; the critical associative mass fraction of ADOC is found to be 0.22%. Notably, ADOC is tested in different solvents, with the final viscosities in clear water, a sodium chloride aqueous solution, and a calcium chloride solution being 58.32, 39.68, and 20.19 mPa·s, respectively. It also demonstrates satisfactory thermal stability and a high shear viscosity recovery rate (90%). Although the molecular structure is disrupted under high shear, the molecules regain a certain entanglement structure when the involved external force disappears, allowing the viscosity to rise after 1 h of shear at a rate of 170 s⁻¹ at 180 ℃. Thixotropy testing reveals a pronounced thixotropic ring. Viscoelasticity testing shows that for the involved ADOC solution, G′ > G”, indicating a robust linear plateau region and high solution viscosity owing to intermolecular associations. The viscosity of 0.6% ADOC after 1 h of shear at 170 s⁻¹ and 180 ℃ was 58.32 mPa·s. These findings demonstrate that ADOC possesses exceptional temperature and shear resistance properties, making it promising for future use in exploiting deep and ultradeep oil reservoirs.

For enhancing the mechanical and fire safety performance of ethylene–vinyl acetate copolymer (EVA) cable materials, IFR (ammonium polyphosphate and pentaerythritol) and MXene were added to EVA and the dispersion of nano-synergistic agent as well as its influence on the flame retardancy, and smoke reduction of EVA cable materials were studied. And the analysis was conducted on the flame retardant mechanism of EVA cable materials. The nano-synergistic agent MXene has the ability to distribute uniformly within the EVA matrix, resulting in EVA/IFR/MXene achieving a tensile strength of 10.6 MPa and an elongation at break of 637.8%. Moreover, the addition of the nano-synergistic agent MXene effectively delayed the thermal degradation of EVA cable materials and improved the amount of residual char. Compared with those of pure EVA, the peak heat release rate and total heat release of the EVA/IFR/MXene cable materials are decreased by 80.9% and 32.8%, respectively. Meanwhile, the emission of harmful gas is also decreased, indicating EVA/IFR/MXene has good fire safety. Thus, the nano-synergistic strategy offers a great method for achieving high-performance EVA cable materials.

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Polydimethylsiloxane (PDMS) is widely used for making flexible waterproof strain sensors, which are often stretched in watery environments. In this study, we used molecular dynamics (MD) simulations to explore the effect of stretching on the anti-permeability of PDMS. The results show that stretching could increase the water permeability of PDMS, however, within a certain simulated time range (250 ps), PDMS can still maintain its waterproofing ability within 30% strain. The interaction energy between water molecules and the PDMS substrate increases with strain. These findings provide insight into the performance of PDMS under mechanical stress in aqueous environments.

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Herein, a series of block copolymers poly(N-(2-methacryloylxyethyl) ethyl pyrrolidone)-block-poly(4-(formaldehyde) phenyl methacrylate) (PNMP₁₃₆-b-PBFMA_m) were developed as the aldehyde precursors D_m. Three kinds of tetraphenylethylene-based dynamic covalent imine copolymers (D_m-A) were generated in situ from the aqueous mixtures of D_m and amino precursors A including 4-(1,2,2-triphenylvinyl) aniline (TPVA), N-(2-aminoethyl)-3-(4-(1,2,2-triphenylvinyl) phenoxy) propenamide (TPVC₂A) and N-(2-aminohexyl)-3-(4-(1,2,2-triphenylvinyl) phenoxy) propenamide (TPVC₆A) at the constant -NH₂/-CHO molar ratio of 1, resulting in D_m-TPVA, D_m-TPVC₂A, and D_m-TPVC₆A, respectively. D_m commonly formed spherical micelles in water, and spherical micelles were also formed by D_m-TPVA, D_m-TPVC₂A, and D_m-TPVC₆A with m below 135. However, D₁₉₄-TPVA, D₁₉₄-TPVC₂A, and D₁₉₄-TPVC₆A preferred to form long and entangled wormlike micelles. This indicates that the morphology of D_m-A aggregates is mainly determined by the degree m of polymerization of PBFMA segment in D_m. The emulsification of D_m, D_m-TPVA, D_m-TPVC₂A, and D_m-TPVC₆A micelles in the dodecane/water systems was depended on the compatibility between oil and copolymers. D_m and D_m-TPVC₆A micelles with m ranging from 44 to 135 were excellent Pickering emulsifiers, favoring the formation of O/W Pickering emulsions.

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With the recent turn toward a green and sustainable environment, the adoption of biopolymers and other natural alternatives to synthetic productions have seen a surge. The production of biopolymers composites offer a proposal for attaining an eco-friendly environment where the fossil fuel reliance for the production of everyday products is reduced. Furthermore, the technological innovations of the present day have encouraged and escalated the introduction of biopolymers in diverse industries and soon may level up their utilization in par with the petroleum-derived ones. Of recent, biopolymer composites combine properties of one biopolymer with another to obtain an enhanced complex that exhibits distinctive features. Biopolymer composites are processed through several methods including infiltration, electrospinning methods and in-situ methods and have achieved considerable global attention been currently utilized in biomedical, automotive, food, construction, and medical industries. Although the efficiency of biopolymer composites has not reached that of their petroleum counterparts, their eco-friendliness, biodegradability, and other qualities will inspire their continual investigation and exploitation. This article focuses on biopolymer composites. It discusses their types, techniques of processing, applications in diverse industries, limitations, and future recommendations.

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Ionic organic dyes are the emerging pollutants that strongly influence to water environment. Adsorption of an anionic dye, Ponceau 4 R on SiO₂-CeO₂ nanocomposites was investigated in the present study. The SiO₂-CeO₂ nanocomposites with nanosilica rice husk were synthesized and examined by XRD, EDX, SEM, FT-IR, and ζ potential. The best conditions for Ponceau 4 R adsorption on SiO₂-CeO₂ were obtained at pH 4, adsorption time 90 min and 10 mg/mL SiO₂-CeO₂ dose. The removal efficiencies and the maximum adsorption capacity of Ponceau 4 R using SiO₂-CeO₂ achieved greater than 99% and 15.63 mg/g, respectively. Adsorption isotherms of Ponceau 4 R and on SiO₂-CeO₂ increased with increasing ionic strengths that were represented by Langmuir, Freundlich, and Temkin models. A pseudo-second-order model was applicable to represent the kinetic of Ponceau 4 R adsorption on SiO₂-CeO₂. Based on the changes in SiO₂-CeO₂ charge by zeta potential and vibrational groups by FT-IR, we demonstrate that electrostatic interactions mainly contributed to the Ponceau 4 R adsorption on SiO₂-CeO₂ surfaces.

Polysaccharide-based drug delivery systems have gained significant attention due to their biocompatibility and potential for targeted therapy. In this study, we utilized Ganoderma lucidum polysaccharides (GLP) as a macromolecular carrier to synthesize polysaccharide drug conjugates by forming ester bonds with 5-fluorouracil (5-FU) derivatives (5-FUAC). This not only improves the solubility and stability of 5-FU but also enhances its targeted delivery to tumor tissues, potentially reducing systemic toxicity. Utilizing Ganoderma lucidum polysaccharides (GLP) as a macromolecular carrier, we successfully synthesized GLP-5-FU conjugates by forming ester bonds with 5-fluorouracil derivatives (5-FUAC). These conjugates were then characterized using spectrum analysis technologies. The drug loading capacities of 5-FU in the GLP-5-FU conjugates were found to be approximately 4.7%. Morphological observations revealed that the GLP-5-FU conjugates had a regular spherical shape. In terms of drug release, 5-FU was found to be released faster at pH 6.8 compared to pH 7.4. To investigate the dynamic viscoelastic behavior of GLP and GLP-5-FU conjugates in water, dynamic rheology analysis was conducted. In terms of cytotoxicity, the GLP-5-FU conjugates exhibited greater inhibition of proliferation compared to 5-FU and GLP alone in HeLa, 786-O, and SKOV3 cells. Furthermore, the GLP-5-FU conjugates showed lower cytotoxicity to 293A cells.

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The current research work aimed to develop, characterize, and assess in vitro cytotoxicity of resveratrol (RSV)-loaded lipid polymer hybrid nanocarriers (LPHN) in glioblastoma multiforme cells. RSV-LPHN was developed by central composite design (CCD). The developed RSV-LPHN were characterized by particle size (PS), polydispersity index (PDI), zeta (ζ) potential, % entrapment efficiency, and in vitro drug release. The surface morphology was studied using SEM and TEM techniques. FTIR, DSC, proton nuclear magnetic resonance (¹H NMR) study, and X-ray diffraction studies (XRD) were also performed. The EE was found in the range of 62–70%, while PDI was between 0.126 and 0.264 exhibiting a monodispersed nature. Zeta potential was found between −15 and −46 mV. Surface morphology through TEM revealed smoothH needle-like structures of the RSV-LPHN. The optimized formulation exhibited nearly 87% drug release over 24 h revealing excellent sustained release behavior in comparison to pure drug. Excellent drug and excipient compatibility was observed in the FTIR study. DSC and ¹H NMR study revealed proper encapsulation of RSV in the lipidic matrix. XRD study confirmed the amorphous nature of the RSV-LPHN. Cellular uptake studies performed in U87 cells showed uptake of 162.26% from RSV-LPHN to control (99.38%) demonstrating maximum cellular internalization. Different concentrations of RSV showed a high percent of inhibition and anticancer activity against the glioblastoma cancer cell line as compared to 5FU. The present study authenticates the potential of RSV-LPHN for efficient management of glioblastoma multiforme.

Present study discloses the investigation of the cloudy formation nature of the mixture of local anesthetic drug tetracaine hydrochloride (TCH) and non-ionic surfactant triton X-100 (TX-100). This investigation was performed in the presence of the potassium electrolytes media (KCl, KBr, K₂SO₄, and K₂HPO₄) with the help of cloud point procedure. In the course of the study, it was observed that the cloud point (CP) values varied with the nature and concentrations of K-electrolytes. In the  concentration effect of K-electrolytes, the CP values of the TX-100 + TCH mixture followed the trend: ({text{CP}}_{text{aq}.text{ KCl}}) > ({text{CP}}_{text{aq}.text{ KBr}}) > ({text{CP}}_{text{aq}. {text{K}}_{2}{text{SO}}_{4}})> ({text{CP}}_{text{aq}. {text{K}}_{2}{text{HPO}}_{4}}) at a specific TCH and TX-100 concentration. The positive values of Gibbs free energy change (({Delta text{G}}_{c}^{o})) were recorded during the phase transformation in the mixture, implying the nonspontaneous process of phase transformation. The magnitudes of (+{Delta text{G}}_{c}^{o}) values were reduced with the rise of the concentration of K-electrolytes. The values of enthalpy change (({Delta text{H}}_{c}^{o})) and entropy change (({Delta text{S}}_{c}^{o})) for phase transition of the TX-100 + TCH mixture were exhibited to be negative in the effect of the concentration of K-electrolytes. On the basis of the ({Delta text{H}}_{c}^{o}) and ({Delta text{S}}_{c}^{o}) values, it has been suggested that the electrostatic interactions (e.g. hydrogen bonding, dipole-dipole), hydrophobic and pi-pi interactions are predominantly working among employed constituents. The information obtained from the current investigation is probably going to be highly beneficial for drug delivery systems as well as pharmaceutical formulations.

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