Iran Polymer and Petrochemical InstituteBasparesh2252-04498120180522Self-assembly of Amphiphilic Azo Polymers in SolutionsSelf-assembly of Amphiphilic Azo Polymers in Solutions316151710.22063/basparesh.2017.1858.1343FAJournal Article20170618Amphiphilic polymers are polymers composed of hydrophilic and the hydrophobic structural units. The hydrophilic groups can be carried by azo chromophores or more commonly attached on the other parts of the polymers. Amphiphilic azo polymers include homopolymers, random copolymers, block and grafted copolymers, star-like polymers, tadpole-shaped polymers and dendritic polymers. Amphiphilic polymers can be considered as synthetic counterparts of ubiquitous amphiphilic compounds in nature such as lipids and proteins. Amphiphilic polymers, especially block copolymers, can form a variety of order aggregates, such as micelles and vesicles. When compared to micelles from traditional surfactants, polymeric self-assemblies have recently been recognized for advantages such as superior stability, toughness and micellization depending on selective solvents. In many instances, the morphology of the polymeric self-assembly and its application are closely related. Thus, controlling the morphology of the assembled structures from block copolymers is of great practical value. Self-assembled polymeric materials with well-defined structures such as spheres, rods, vesicles, lamellas and other nanostructures have attracted increasing interests recently due to their potential applications in biomedical engineering, electronics and optics. The self-assembled structures of azo polymers can undergo structural changes both in solution and in the solid state when triggered by light or other external stimuli. Understanding the self-assembling processes can lead to the development of photo responsive materials with new functions for future applications. In this review the self-assembly of amphiphilic azo polymers in solutions are reported.Amphiphilic polymers are polymers composed of hydrophilic and the hydrophobic structural units. The hydrophilic groups can be carried by azo chromophores or more commonly attached on the other parts of the polymers. Amphiphilic azo polymers include homopolymers, random copolymers, block and grafted copolymers, star-like polymers, tadpole-shaped polymers and dendritic polymers. Amphiphilic polymers can be considered as synthetic counterparts of ubiquitous amphiphilic compounds in nature such as lipids and proteins. Amphiphilic polymers, especially block copolymers, can form a variety of order aggregates, such as micelles and vesicles. When compared to micelles from traditional surfactants, polymeric self-assemblies have recently been recognized for advantages such as superior stability, toughness and micellization depending on selective solvents. In many instances, the morphology of the polymeric self-assembly and its application are closely related. Thus, controlling the morphology of the assembled structures from block copolymers is of great practical value. Self-assembled polymeric materials with well-defined structures such as spheres, rods, vesicles, lamellas and other nanostructures have attracted increasing interests recently due to their potential applications in biomedical engineering, electronics and optics. The self-assembled structures of azo polymers can undergo structural changes both in solution and in the solid state when triggered by light or other external stimuli. Understanding the self-assembling processes can lead to the development of photo responsive materials with new functions for future applications. In this review the self-assembly of amphiphilic azo polymers in solutions are reported.http://basparesh.ippi.ac.ir/article_1517_7818d9afde9195ad0372e2ccb6d38739.pdfIran Polymer and Petrochemical InstituteBasparesh2252-04498120180522Investigation on Neutral Polymeric Bonding Agents in Solid Propellant Composites and Plastic Bonded ExplosivesInvestigation on Neutral Polymeric Bonding Agents in Solid Propellant Composites and Plastic Bonded Explosives1730148810.22063/basparesh.2017.1488FAAbbas KebritchiJournal Article20170409Bonding agent is one of the important additives in composite solid propellants (CSPs) and plastic bonded explosives (PBXs) that plays critical role in improving the mechanical properties. Bonding agents are usually organic small molecules which are added to CSPs and PBXs formulations with neutral polymeric binders at low contents. Nevertheless, for CSPs and PBXs formulations with energetic polymeric binders, conventional small molecule bonding agents isn't usefull. Neutral polymeric bonding agents (NPBAs) are a novel family of bonding agents, which are vital in formulations containing polar fillers dispersed in polar binders. In this study, by necessity synthesis, the molecular design, and probable mechanisms of interactions and most important reported results of NPBAs are presented. The studies showed that the use of NPBAs in CSPs and PBXs formulations, with much smaller amount than that of monomeric bonding agents in conventional formulations, has significant effect on improving the mechanical properties. The effectiveness of NPBAs in modifying the mechanical properties of composite solid propellants was comparable or even better than the effect of solid particles pre-coating.Bonding agent is one of the important additives in composite solid propellants (CSPs) and plastic bonded explosives (PBXs) that plays critical role in improving the mechanical properties. Bonding agents are usually organic small molecules which are added to CSPs and PBXs formulations with neutral polymeric binders at low contents. Nevertheless, for CSPs and PBXs formulations with energetic polymeric binders, conventional small molecule bonding agents isn't usefull. Neutral polymeric bonding agents (NPBAs) are a novel family of bonding agents, which are vital in formulations containing polar fillers dispersed in polar binders. In this study, by necessity synthesis, the molecular design, and probable mechanisms of interactions and most important reported results of NPBAs are presented. The studies showed that the use of NPBAs in CSPs and PBXs formulations, with much smaller amount than that of monomeric bonding agents in conventional formulations, has significant effect on improving the mechanical properties. The effectiveness of NPBAs in modifying the mechanical properties of composite solid propellants was comparable or even better than the effect of solid particles pre-coating.http://basparesh.ippi.ac.ir/article_1488_3a92e3a44f1de8addf8972f799a1fc94.pdfIran Polymer and Petrochemical InstituteBasparesh2252-04498120180522Morphology, Thermal, Mechanical and Electrical Properties of Poly(acrylonitrile-butadiene-styrene)/Carbon Nanotubes Nanocomposites: A ReviewMorphology, Thermal, Mechanical and Electrical Properties of Poly(acrylonitrile-butadiene-styrene)/Carbon Nanotubes Nanocomposites: A Review3144151110.22063/basparesh.2017.1511FAZahra SoheilpourMohammad Razavi NouriJournal Article20170426Rapid development in producing carbon nanotubes (CNTs) thermoplastics nanocomposites have been observed in the past two decades. This is because the addition of a small amount of CNTs could increase the thermal stability, flame retardency, conductivity, Young's modulus, impact resistance and sound-proofing of the polymer-based nanocomposites. One of the challenging issues for obtaining the full performance of the nanocomposites is the dispersion of CNTs in a polymeric matrix. There are several methods to achieve a good dispersion of the nanofiller throughout the polymer matrices. It should be noted that the type of method used could play an important role in dispersion of CNTs. Poly(acrylonitrile-butadiene-styrene) (ABS)/CNTs nanocomposites are used in various industries, for instance in manufacturing of the electronic devices. In recent years, there has been an increasing interest in additive manufacturing technologies in which fused deposition modeling (FDM) has the fastest growth rate by using thermoplastics such as ABS as one of the most applicable materials for this processing method. In this paper, our aim is to present some information on ABS/CNTs nanocomposites prepared using different methods and with studies on their morphologies as well as thermal, mechanical and electrical properties by reviewing the recently related published literature.Rapid development in producing carbon nanotubes (CNTs) thermoplastics nanocomposites have been observed in the past two decades. This is because the addition of a small amount of CNTs could increase the thermal stability, flame retardency, conductivity, Young's modulus, impact resistance and sound-proofing of the polymer-based nanocomposites. One of the challenging issues for obtaining the full performance of the nanocomposites is the dispersion of CNTs in a polymeric matrix. There are several methods to achieve a good dispersion of the nanofiller throughout the polymer matrices. It should be noted that the type of method used could play an important role in dispersion of CNTs. Poly(acrylonitrile-butadiene-styrene) (ABS)/CNTs nanocomposites are used in various industries, for instance in manufacturing of the electronic devices. In recent years, there has been an increasing interest in additive manufacturing technologies in which fused deposition modeling (FDM) has the fastest growth rate by using thermoplastics such as ABS as one of the most applicable materials for this processing method. In this paper, our aim is to present some information on ABS/CNTs nanocomposites prepared using different methods and with studies on their morphologies as well as thermal, mechanical and electrical properties by reviewing the recently related published literature.http://basparesh.ippi.ac.ir/article_1511_7e60829ff087d62f1333ea775f59bcf6.pdfIran Polymer and Petrochemical InstituteBasparesh2252-04498120180522Study of Liquid-crystalline Structures in Polymers and their Effects on the Properties of Textile FibersStudy of Liquid-crystalline Structures in Polymers and their Effects on the Properties of Textile Fibers4556151810.22063/basparesh.2017.1874.1346FAJournal Article20170527A three-phase model is often used to investigate the structure of semicrystalline polymers. Some of the polymeric chains lay in-between crystalline and amorphous phases so-called liquid-crystal structures. Liquid-crystalline polymers consist mainly of one-dimensional rod-like groups placed in the main chain or side chain. A great number of liquid-crystalline states have been reported, ranging from those exhibiting only long-range orientational order, nematic and cholesteric phases, to those exhibiting both long-range orientational and positional order, the smectic phases. Liquid crystalline structures can be organized into three classes, lyotropic, thermotropic, and mesogenic side group compositions. As the liquid-crystalline structures consist of polymeric chains with para-crystalline order and has a key role on the ultimate properties of textile fibers, it will be important to learn about this structure and the post-treatment changes such as drawing and thermal annealing that occur in this structure. Designing new polymer processes or improving upon old ones can only be achieved by exactly knowing the mechanisms of microstructure development and the mesomorphic transitions in the textile fibers exhibiting liquid-crystalline behaviour.A three-phase model is often used to investigate the structure of semicrystalline polymers. Some of the polymeric chains lay in-between crystalline and amorphous phases so-called liquid-crystal structures. Liquid-crystalline polymers consist mainly of one-dimensional rod-like groups placed in the main chain or side chain. A great number of liquid-crystalline states have been reported, ranging from those exhibiting only long-range orientational order, nematic and cholesteric phases, to those exhibiting both long-range orientational and positional order, the smectic phases. Liquid crystalline structures can be organized into three classes, lyotropic, thermotropic, and mesogenic side group compositions. As the liquid-crystalline structures consist of polymeric chains with para-crystalline order and has a key role on the ultimate properties of textile fibers, it will be important to learn about this structure and the post-treatment changes such as drawing and thermal annealing that occur in this structure. Designing new polymer processes or improving upon old ones can only be achieved by exactly knowing the mechanisms of microstructure development and the mesomorphic transitions in the textile fibers exhibiting liquid-crystalline behaviour.http://basparesh.ippi.ac.ir/article_1518_9280809d0ee4551f0d14e7dc315e4d98.pdfIran Polymer and Petrochemical InstituteBasparesh2252-04498120180522Isolation, Purification and Characterization of Non-cellulosic Water-soluble Polysaccharides: A ReviewIsolation, Purification and Characterization of Non-cellulosic Water-soluble Polysaccharides: A Review5768148710.22063/basparesh.2017.1487FAJournal Article20170427Nowadays, finding biopolymers with desirable properties for wide industrial applications is one of the important issues to research around the world. Polysaccharides are the biopolymers which have a variety of applications in different industries and in the field of medicine. Abundance, biodegradability, renewability and being natural make them appropriate materials to replace some of petroleum-based products and to be used for the applications requiring biocompatibility. Due to their structural variations in nature, polysaccharides' properties are immense. In order to explain and improve the properties, structural characterization of polysaccharides is necessary and is of interest for the researchers nowadays. Because of structural varieties of non-cellulosic water-soluble polysaccharides, identification of the polysaccharides' structure for finding their medical properties is also of importance in the research studies. The first step in structural characterization of water-soluble polysaccharide is to isolate and purify the polysaccharide, as various sources of polysaccharides made by plants, animals and bacteria have different impurities. Every non-polysaccharide material in the samples requires specific method to be isolated. Different method and tools exist to characterize the chemical structure of these biopolymers. This review introduces the common methods and tests used for isolation, purification and structural characterization of the water-soluble polysaccharides.Nowadays, finding biopolymers with desirable properties for wide industrial applications is one of the important issues to research around the world. Polysaccharides are the biopolymers which have a variety of applications in different industries and in the field of medicine. Abundance, biodegradability, renewability and being natural make them appropriate materials to replace some of petroleum-based products and to be used for the applications requiring biocompatibility. Due to their structural variations in nature, polysaccharides' properties are immense. In order to explain and improve the properties, structural characterization of polysaccharides is necessary and is of interest for the researchers nowadays. Because of structural varieties of non-cellulosic water-soluble polysaccharides, identification of the polysaccharides' structure for finding their medical properties is also of importance in the research studies. The first step in structural characterization of water-soluble polysaccharide is to isolate and purify the polysaccharide, as various sources of polysaccharides made by plants, animals and bacteria have different impurities. Every non-polysaccharide material in the samples requires specific method to be isolated. Different method and tools exist to characterize the chemical structure of these biopolymers. This review introduces the common methods and tests used for isolation, purification and structural characterization of the water-soluble polysaccharides.http://basparesh.ippi.ac.ir/article_1487_0c2e7bcf25c6bd6d03c13cc21f1c2e05.pdfIran Polymer and Petrochemical InstituteBasparesh2252-04498120180522The Effect of Natural Stabilizers on Melt Processing of Polyethylene: A ReviewThe Effect of Natural Stabilizers on Melt Processing of Polyethylene: A Review6979152310.22063/basparesh.2017.1895.1351FAAzar ZareJournal Article20170701Polyethylene is degraded by exposure to heat, shear rate and oxygen in melting process. In order to achieve the polyethylene melt stability against thermal oxidation phenomena, the use of stabilizers is a key factor for the preservation of physical and chemical properties. In recent years, various natural stabilizers during the melting process of polyethylene have been of interest to the researchers, since during storage of food in packaging containers produced with synthetic stabilizers, these additives can migrate to food and endanger human health. Some natural stabilizers are phenolic compounds in plant sources that have higher resistance to synthetic stabilizers at high temperatures and have higher melt stability. In this paper, the effect of several natural stabilizers on the polyethylene melt stability is investigated. Stability performance is determined by measuring rheological properties, thermal oxidation stability and polymer color. The results of the flow index measurement of polyethylene containing these natural stabilizers show that the viscosity changes are insignificant during the melt process, but the synthetic stabilizers undergo changes in their molten flow index and it is degraded during the melt process. On the other hand, the evaluation of yellowness index shows that the natural stabilizer affects the color of polyethylene. However, despite this slight weakness of natural stabilizers, it can be used to prevent heat damage in cases where the color of the product is a secondary issue. As a result, natural stabilizers can be a good alternative to synthetic stabilizers during the melting process of polyethylene.Polyethylene is degraded by exposure to heat, shear rate and oxygen in melting process. In order to achieve the polyethylene melt stability against thermal oxidation phenomena, the use of stabilizers is a key factor for the preservation of physical and chemical properties. In recent years, various natural stabilizers during the melting process of polyethylene have been of interest to the researchers, since during storage of food in packaging containers produced with synthetic stabilizers, these additives can migrate to food and endanger human health. Some natural stabilizers are phenolic compounds in plant sources that have higher resistance to synthetic stabilizers at high temperatures and have higher melt stability. In this paper, the effect of several natural stabilizers on the polyethylene melt stability is investigated. Stability performance is determined by measuring rheological properties, thermal oxidation stability and polymer color. The results of the flow index measurement of polyethylene containing these natural stabilizers show that the viscosity changes are insignificant during the melt process, but the synthetic stabilizers undergo changes in their molten flow index and it is degraded during the melt process. On the other hand, the evaluation of yellowness index shows that the natural stabilizer affects the color of polyethylene. However, despite this slight weakness of natural stabilizers, it can be used to prevent heat damage in cases where the color of the product is a secondary issue. As a result, natural stabilizers can be a good alternative to synthetic stabilizers during the melting process of polyethylene.http://basparesh.ippi.ac.ir/article_1523_e478dca083ffa2116026488d9c5b2b25.pdfIran Polymer and Petrochemical InstituteBasparesh2252-04498120180522An Overview on Polymer Electrolytes for Dye-sensitized Solar CellsAn Overview on Polymer Electrolytes for Dye-sensitized Solar Cells8089152210.22063/basparesh.2017.1998.1374FAMozhgan HosseinnezhadAcademic StaffJournal Article20170904Today's energy crisis is one of the most important concerns of mankind. As the population grows, the need for sustainable and low-risk energy is felt more and more. One of the most accessible and renewable sources of energy is the sun. Solar cells are used to convert solar energy to electrical energy. So far, solar cells have been divided into three generations of silicon solar cells, thin-film solar cells, and third generation solar cells. Dye-sensitized solar cells, also known as an important category of third-generation solar cells, have five main components, including the anode electrode, dye, metal oxide, electrolyte, and counter electrode. An important component in dye-sensitized solar cells (DSSCs), electrolytes, is the role of dye electron supply to return to the ground state. Electrolytes used in dye-sensitized solar cells are divided into two classes of liquid and polymer electrolytes. Polymer electrolytes are an interesting technology for increasing of fastness of dye-sensitized solar cells. There are four main kinds of polymer electrolytes as thermoplastic polymers, thermosetting polymer, composites and ionic liquid polymers. The aim of this article is introduce and describe the components of the polymer electrolytes including materials and components. Finally, some brief performance and general perspectives on polymer electrolytes are presented.Today's energy crisis is one of the most important concerns of mankind. As the population grows, the need for sustainable and low-risk energy is felt more and more. One of the most accessible and renewable sources of energy is the sun. Solar cells are used to convert solar energy to electrical energy. So far, solar cells have been divided into three generations of silicon solar cells, thin-film solar cells, and third generation solar cells. Dye-sensitized solar cells, also known as an important category of third-generation solar cells, have five main components, including the anode electrode, dye, metal oxide, electrolyte, and counter electrode. An important component in dye-sensitized solar cells (DSSCs), electrolytes, is the role of dye electron supply to return to the ground state. Electrolytes used in dye-sensitized solar cells are divided into two classes of liquid and polymer electrolytes. Polymer electrolytes are an interesting technology for increasing of fastness of dye-sensitized solar cells. There are four main kinds of polymer electrolytes as thermoplastic polymers, thermosetting polymer, composites and ionic liquid polymers. The aim of this article is introduce and describe the components of the polymer electrolytes including materials and components. Finally, some brief performance and general perspectives on polymer electrolytes are presented.http://basparesh.ippi.ac.ir/article_1522_e3325f81db2230fd7839d346de7754e7.pdfIran Polymer and Petrochemical InstituteBasparesh2252-04498120180522Flexible Acoustic Polyurethane Foam: An Overview of Physical Structure and Chemical PropertiesFlexible Acoustic Polyurethane Foam: An Overview of Physical Structure and Chemical Properties90100152110.22063/basparesh.2017.1960.1365FASahar Abdollahi BaghbanManouchehr Khorasaniamirkabir university of trchnologyJournal Article20170812Noise is one of the most disturbing environmental problems of today's societies, and this problem becomes more serious with increasing traffic volumes and rapid expansion of industries. One of the ways to solve this problem is to increase the sound absorption coefficient of porous structure materials used as acoustic absorbers. Over the past decade, flexible polyurethane foam has been recognized in the acoustic absorbing industry as efficient materials due to its effective damping power, low density, high formability and easy production. The most important feature of flexible polyurethane foams is the presence of open porosity cavities, which not only control the mechanical properties of foam, but also their sound insulation properties. The purpose of this study is to review the applications, the development of polyurethane foam, the chemical and physical structure and the factors affecting the properties of foams due to their acoustic absorption and mechanical energy loss of sound waves. Considering the role of polyurethane foam as sound insulation, the focus of this study will be on the behavior of polyurethane foam as sound insulation, so some physical concepts related to sound will also be expressed.Noise is one of the most disturbing environmental problems of today's societies, and this problem becomes more serious with increasing traffic volumes and rapid expansion of industries. One of the ways to solve this problem is to increase the sound absorption coefficient of porous structure materials used as acoustic absorbers. Over the past decade, flexible polyurethane foam has been recognized in the acoustic absorbing industry as efficient materials due to its effective damping power, low density, high formability and easy production. The most important feature of flexible polyurethane foams is the presence of open porosity cavities, which not only control the mechanical properties of foam, but also their sound insulation properties. The purpose of this study is to review the applications, the development of polyurethane foam, the chemical and physical structure and the factors affecting the properties of foams due to their acoustic absorption and mechanical energy loss of sound waves. Considering the role of polyurethane foam as sound insulation, the focus of this study will be on the behavior of polyurethane foam as sound insulation, so some physical concepts related to sound will also be expressed.http://basparesh.ippi.ac.ir/article_1521_fd40389c0f38ac1927fcfb68c492a2f9.pdfIran Polymer and Petrochemical InstituteBasparesh2252-04498120180522reportsreports1011171558FAJournal Article19700101http://basparesh.ippi.ac.ir/article_1558_4d885a35eab81b388426e1ad783036f9.pdf