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Showing posts with the label Condensation polymers

Investigation of Extensional Flow Behavior of Polyethylene Melts through Birefringence by using Extrusion Cross-slot Die

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  Academic Journal of Polymer Science - Juniper Publishers                                                            Abstract Flow parameters of polymers melt under steady state condition in shear are required to assess flow behaviour of the molten material in the die or downstream operations. Very often this is not sufficient to have a full understanding of the polymer processability, and additional information of flow response in extension is also needed. In this paper, the extensional properties of two molten polyethylene have been investigated by measuring stress response when a high extensional deformation is applied in a cross-slot die. Flow induced birefringence analysis and stress-optical rule are applied to determine rheological properties. Two polyethylene’s with similar rheology in shear but different molecular structure (...

Polymeric Based Materials via Palladium- Catalyzed Polycondensation

   JUNIPER PUBLISHERS-   ACADEMIC JOURNAL OF POLYMER SCIENCE Abstract The significant access to the structurally pure, high molar mass, N-containing polymers via palladium-catalyzed polycondensation of various aromatic diamines with various aromatic dibromo compounds is an interesting target. One of the major advantages is to apply inexpensive monomers; aromatic amines and aromatic bromides. Furthermore, many diamines are readily available or easy to synthesize giving fast access to numerous new functionalized polymers either by applying amino-functionalized or bromo-functionalized monomers to optimize and improve the polymer properties. With the increasing demand for different functionalized polymers, the focus of relevant studies has been to generate polymers with improved properties by palladium-catalyzed polycondensation. A series of poly(imino ether)s (PIEs), poly(imino ketone)s (PIKs), poly(imino azobenzene)s (PIAzos), poly(imino acridine)s (PIAcs), poly(imino fluor...

Research Progress of Semi-Aromatic Copolyamides: Structure-Property Relationship

       JUNIPER PUBLISHERS-   ACADEMIC JOURNAL OF POLYMER SCIENCE Abstract Semi-aromatic copolyamides owing to both possessing the machinability of aliphatic polyamides and the high temperature resistance of aromatic polyamides, were widely used in automotive and electronic fields. To better summarizes the research on the structure-property relationship of semi-aromatic copolyamides, the review was carried out from three aspects: synthesis, structure characterization and structure-property relationship. The study of structure-property relationship can be applied to the modification process of semi-aromatic copolyamides, and it can shed light on the design and actual production process. Keywords:  Copolyamides; Solution Polycondensation; Sequence structure; Structure-Property Relationship Introduction Semi-aromatic copolyamides contain both aliphatic and aromatic segments, therefore possess some unique properties, such as high mechanical strength, high temper...

Industrial Scalable Additives for Enhanced Decomposition of Plastic Waste Through Photocatalysis

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     JUNIPER PUBLISHERS-   ACADEMIC JOURNAL OF POLYMER SCIENCE Abstract Polymer pollution is a dangerous environmental problem that can lead to the spread of toxic chemicals and microplastics throughout aquatic biomes. Commonly littered plastic from consumer goods and products with a limited or single use can be embedded with photocatalysts to avoid an increase in the amount of plastic present in Earth’s bodies of water. The photocatalyst nanoparticles, less than 100 nm particle size, were integrated into polyethylene terephthalate, high-density polyethylene, low-density polyethylene, and polystyrene and exposed under ultraviolet light over two independent experimental trials examining both the environmental factors impacting decay and the physical parameters required to implement this solution on a large scale. The plastics were chosen due to their prolific use in items such as grocery bags, bottles, and packaging. The first half of the project examined the effects ...