38 research outputs found

    Modeling and Optimizing of Producing Recycled PET from Fabrics Waste via Falling Film-Rotating Disk Combined Reactor

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    Recycling and reusing of poly (ethylene terephthalate) (PET) fabrics waste are essential for reducing serious waste of resources and environmental pollution caused by low utilization rate. The liquid-phase polymerization method has advantages of short process flow, low energy consumption, and low production cost. However, unlike prepolymer, the material characteristics of PET fabrics waste (complex composition, high intrinsic viscosity, and large quality fluctuations) make its recycling a technique challenge. In this study, the falling film-rotating disk combined reactor is proposed, and the continuous liquid-phase polymerization is modeled by optimizing and correcting existing models for the final stage of PET polymerization to improve the product quality in plant production. Through modeling and simulation, the weight analysis of indexes closely related to the product quality (intrinsic viscosity, carboxyl end group concentration, and diethylene glycol content) was investigated to optimize the production process in order to obtain the desired polymer properties and meet specific product material characteristics. The model could be applied to other PET wastes (e.g., bottles and films) and extended to investigate different aspects of the recycling process

    Efficient organic solar cells enabled by simple non-fused electron donors with low synthetic complexity

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    Abstract Fused‐ring electron donors boost the efficiency of organic solar cells (OSCs), but they suffer from high cost and low yield for their large synthetic complexity (SC > 30%). Herein, the authors develop a series of simple non‐fused‐ring electron donors, PF1 and PF2, which alternately consist of furan‐3‐carboxylate and 2,2′‐bithiophene. Note that PF1 and PF2 present very small SC of 9.7% for their inexpensive raw materials, facile synthesis, and high synthetic yield. Compared to their all‐thiophene‐backbone counterpart PT‐E, two new polymers feature larger conjugated plane, resulting in higher hole mobility for them, especially a value up to ≈10 −4 cm 2 V −1 ·s for PF2 with longer alkyl side chain. Meanwhile, PF1 and PF2 exhibit larger dielectric constant and deeper electronic energy level versus PT‐E. Benefiting from the better physicochemical properties, the efficiencies of PF1‐ and PF2‐based devices are improved by ≈16.7% and ≈71.3% relative to that PT‐E‐based devices, respectively. Furthermore, the optimized PF2‐based devices with introducing PC 71 BM as the third component deliver a higher efficiency of 12.40%. The work not only indicates that furan‐3‐carboxylate is a simple yet efficient building block for constructing non‐fused‐ring polymers but also provides a promising electron donor PF2 for the low‐cost production of OSCs.A simple structure non‐fused‐ring electron donor PF2 alternately consisting of furan‐3‐carboxylate and 2,2′‐bithiophene presents very small synthetic complexity of 9.7% as well as low material cost of ≈19.0 $ g −1 . More importantly, PF2 delivers a high efficiency of 12.4% coupled with strong operational stability. imag

    Effect of Azo Dyes on the Thermal Degradation of Post-consumer Polyester Fabrics

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    Thermogravimetric analysis(TGA) and pyrolysis gas chromatography mass spectrometry (Py-GC-MS) investigations were carried out on the thermal degradation of white and red post-consumer polyester fabrics. The results show that red PET fabrics which was dyed with C.I. Disperse red 167 for its typical azo structure exhibits larger activation energy compared with white PET. The addition of azo dyes displays an inhibiting effect on the deep pyrolysis and the formation of biphenyl and bis(2-hydroxybutyl) terephthalate produced by the free radical mechanism

    Effect of Azo Dyes on the Thermal Degradation of Post-consumer Polyester Fabrics

    No full text
    Thermogravimetric analysis(TGA) and pyrolysis gas chromatography mass spectrometry (Py-GC-MS) investigations were carried out on the thermal degradation of white and red post-consumer polyester fabrics. The results show that red PET fabrics which was dyed with C.I. Disperse red 167 for its typical azo structure exhibits larger activation energy compared with white PET. The addition of azo dyes displays an inhibiting effect on the deep pyrolysis and the formation of biphenyl and bis(2-hydroxybutyl) terephthalate produced by the free radical mechanism

    Chain Extension and Thermal Behavior of Recycled Poly(Ethylene Terephthalate) Modified by Reactive Extrusion with Triphenyl Phosphite

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    Reactive extrusion experiments of recycled PET fabrics (R-PET) were carried out in a Haake torque rheometer with triphenyl phosphite (TPP) and thermal behavior of modified R-PET was investigated by differential scanning calorimetry (DSC). The reaction mechanism which TPP acts as a cross-linker is verified by the experiment of phosphorus elemental analysis. DSC results show the presence of reaction residues may not modify melting temperature Tm and crystallization temperature Tc is controlled by the combined effect of molecular weight and reaction residues

    Chain Extension and Thermal Behavior of Recycled Poly(Ethylene Terephthalate) Modified by Reactive Extrusion with Triphenyl Phosphite

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    Reactive extrusion experiments of recycled PET fabrics (R-PET) were carried out in a Haake torque rheometer with triphenyl phosphite (TPP) and thermal behavior of modified R-PET was investigated by differential scanning calorimetry (DSC). The reaction mechanism which TPP acts as a cross-linker is verified by the experiment of phosphorus elemental analysis. DSC results show the presence of reaction residues may not modify melting temperature Tm and crystallization temperature Tc is controlled by the combined effect of molecular weight and reaction residues

    Management of subdural effusion and hydrocephalus following decompressive craniectomy for posttraumatic cerebral infarction in a patient with traumatic brain injury: a case report

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    Abstract Background Subdural effusion with hydrocephalus (SDEH) is a rare complication of traumatic brain injury, especially following decompressive craniectomy (DC) for posttraumatic cerebral infarction. The diagnosis and treatment are still difficult and controversial for neurosurgeons. Case presentation A 45-year-old man developed traumatic cerebral infarction after traumatic brain injury and underwent DC because of the mass effect of cerebral infarction. Unfortunately, the complications of traumatic subdural effusion (SDE) and hydrocephalus occurred in succession following DC. Burr-hole drainage and subdural peritoneal shunt were performed in sequence because of the mass effect of SDE, which only temporarily improved the symptoms of the patient. Cranioplasty and ventriculoperitoneal shunt were performed ultimately, after which SDE disappeared completely. However, the patient remains severely disabled, with a Glasgow Outcome Scale of 3. Conclusions It is important for neurosurgeons to consider the presence of accompanying hydrocephalus when treating patients with SDE. Once the diagnosis of SDEH is established and the SDE has no mass effect, timely ventriculoperitoneal shunt may be needed to avoid multiple surgical procedures, which is a safe and effective surgical method to treat SDEH

    MTAP-ANRIL gene fusion promotes melanoma epithelial-mesenchymal transition-like process by activating the JNK and p38 signaling pathways

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    Abstract Gene fusions caused by cytogenetic aberrations play important roles in the initiation and progression of cancers. The recurrent MTAP-ANRIL fusion gene was reported to have a frequency of greater than 7% in melanoma in our previous study. However, its functions remain unclear. Truncated MTAP proteins resulting from point mutations in the last three exons of MTAP can physically interact with the wild-type MTAP protein, a tumor suppressor in several human cancers. Similarly, MTAP-ANRIL, which is translated into a truncated MTAP protein, would influence wild-type MTAP to act as an oncogene. Here, we found that MTAP-ANRIL gene fusion downregulated the expression of wild-type MTAP and promoted epithelial-mesenchymal transition-like process through the activation of JNK and p38 MAPKs in vitro and in vivo. Our results suggest that MTAP-ANRIL is a potential molecular prognostic biomarker and therapeutic target for melanoma
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