Synthesis, Modification, and Applications of Poly(vinyl chloride) (PVC)

Polymer-Plastics Technology and Materials, Journal Year: 2024, Volume and Issue: unknown, P. 1 - 40

Published: Nov. 1, 2024

One of the polymers with biggest production volume is poly(vinyl chloride) (PVC) considering their versatility, durability, lightweight, as well low cost production, plastics have recently become an essential part everyone's daily life. However, increased and usage poses significant environmental problems because incomplete utilization, a lengthy biodegradation period, detrimental effects on living things. This study examines latest findings in PVC research, including its properties, polymerization, modification, recycling, diverse applications. It has been proposed that during along application both inorganic organic thermal stabilizers, can mitigate some basic limiting characteristics PVC. chemistry extended by vast continuous study, mainly chemical transformations this polymeric material. describes modification using different materials active modifying agent. The latter included substitutions, modifications, nucleophilic radicals, removal or dehydrochlorination, grafting polymerizations. PVC's consequences are examined, overview functionalization provided article, discussion main reactivity trends lens recycling.

Language: Английский

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Thermodynamic and Technological Compatibility of Polyvinyl Chloride, Thermoplastic Polyurethane, and Bio-Plasticizer Blends

Polymers, Journal Year: 2025, Volume and Issue: 17(9), P. 1149 - 1149

Published: April 23, 2025

Polymer blending enhances material properties by combining different polymers, which requires careful consideration of both thermodynamic and technological compatibility. This study investigates the compatibility polyvinyl chloride (PVC), thermoplastic polyurethane (TPU), a bio-plasticizer in blends produced via roll milling at various mixing ratios. Compatibility morphology were analyzed using thermally stimulated discharge (TSD), dynamic mechanical analysis (DMA), scanning electron microscopy (SEM), while thermal assessed testing thermogravimetric (TGA). The PVC/TPU (100/30) blend exhibited superior phase over (100/50), as indicated single relaxation peak TSD DMA, along with more homogeneous enhanced tensile properties. PVC/TPU/bio-plasticizer (100/20/50) showed well-balanced performance improved homogeneity. maxima trends for TPU/bio-plasticizer highlighted bio-plasticizer’s dual role enhancing flexibility low concentrations restricting molecular mobility higher concentrations. TGA revealed TPU’s positive effect on PVC’s degradation profile, reduced stability. These findings demonstrate that PVC, TPU, creates compatible materials diverse properties, making them suitable industrial applications.

Language: Английский

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Recyclability of Plastics from Waste Mobile Phones According to European Union Regulations REACH and RoHS

Materials, Journal Year: 2025, Volume and Issue: 18(9), P. 1979 - 1979

Published: April 27, 2025

Small waste from electrical and electronic equipment (WEEE) such as mobile phones are rich in plastic components. Recycling is particularly challenging, since the main interest for recyclers printed circuit boards, valuable metals, while components usually destined thermal recovery. This study dedicated to assessment of recyclability potential fractions end-of-life (EoL) according European Union's (EU) Restriction Hazardous Substances (RoHS) Registration, Evaluation, Authorization Chemicals (REACH) directives. A total 275 items (inventoried casings, frames, screens) were dismantled 100 EoL analyzed identify type abundance polymers via Fourier-transform infrared spectroscopy (FTIR) presence hazardous elements Br, Cl, Pb, Cd X-ray fluorescence (XRF). Polycarbonate (PC) (57% samples) polymethyl methacrylate (PMMA) (27% items) identified most common prevalent polymers. In total, 67% contained Cl (0.84-40,700 mg/kg), 26% Br (0.08-2020 mg/kg). Hg was detected only one item (17 Cr found 17% items, with concentrations between 0.37 mg/kg 915 mg/kg, Pb 15% low (1-90 conclusion, present (with higher values smartphones), their below regulatory limits, suggesting compliance recycling regulations EU.

Language: Английский

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Microstructure Study and Kinetic of Conjugated Polyene Formation in Alkaline Dehydrochlorination of PVC

Journal of Applied Polymer Science, Journal Year: 2025, Volume and Issue: unknown

Published: May 5, 2025

ABSTRACT Polyvinyl chloride (PVC) is a widely used plastic; yet, its recycling remains challenging due to the release of hazardous chlorine compounds during conventional processing. This study investigates alkaline dehydrochlorination PVC using KOH and NaOH in dimethylformamide (DMF)/ethylene glycol (EG) system at 100°C–140°C. The effects temperature, base concentration, type (KOH vs. NaOH) on PVC's microstructure kinetics were examined. Fourier‐transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR), ultraviolet–visible (UV–Vis) analyses, along with color changes, confirmed successful dehydrochlorination. Microstructural analysis revealed progressive decrease meso–meso (mm, initial: 0.242) increase racemic–racemic (rr, 0.314) triad sequences After 40 min, mm reached 0.163 (KOH) 0.117 (NaOH); rr increased 0.379 0.407 (NaOH). process occurred ratio ~ 9:1 via simultaneous E2 S N 2 mechanisms. Kinetic studies UV–Vis yielded activation energies 21.6 22.03 kcal mol −1 for polyene double‐bond formation, respectively, Arrhenius constants 2.96 × 10 5 2.27 6 Alkaline was found be faster more direct than thermal A reaction order 1.0 respect concentration supported mechanism. efficient removing HCl from PVC. work introduces stereoselective process, achieving lower environmental compatibility compared methods, offering sustainable alternative recycling.

Language: Английский

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