Introduction to materials science chapter 19, thermal properties 3 heat capacity heat capacity is a measure of the ability of the material to absorb thermal energy. Concrete, plywood, and fiberglass are examples of composite materials. Explain how polymer structure determines material properties, such as flexibility or transparency. The basic structure of plastics or polymers is given by macromolecule chains, formulated from monomer units by chemical reactions. Polymers are materials with a seemingly limitless range of characteristics and colors. These small units are repeated throughout the macromolecule chain. Polymer waste is a serious burden for the environment because common organisms. Structure and properties of polymers pavel kratochvil institute of macromolecular chemistry, academy of sciences of the czech republic, prague, czech republic keywords. Crystal structure stressstrain behavior creep, fracture, fatigue, and wear of materials. That said, as explained in chapter 3, the requisite material properties that are to be optimized cannot be measured by the usual quasistatic measures of mechanical behavior.
In fact, the basic molecular structure of all plant and animal life is similar to that of a synthetic polymer. Moreover, synthetic polymers are readily available with abundant species and multiple functional groups, which not only reduces. These species grow naturally in the semiarid subsaharan regions of africa. Lecture notes polymer physics materials science and. With such an understanding, the piping designer can use the properties of the material. Items such as disposable coffee cups, plastic food boxes, plastic cutlery and packing foam are made from ps.
Macromolecule, polymer, monomer, polymerization, statistical coil, material, polymer blend, copolymerization, modulus, glass transition, properties of. These are formed from two or more materials, producing properties not found in any single material. Acrylic is an economical, general purpose material used in a wide variety of applications, including. Materials science and technology is a multidisciplinary approach to science that involves designing, choosing, and using three major classes of materials metals, ceramics, and polymers plastics. The main idea in developing composites is to blend the properties of different materials. Polystyrene is commonly recycled, but is difficult to do. Thermoset polymers have a permanent irreversible polymerization. Pdf physical and mechanical properties of polymer composites.
Introduction the technological process of rubber blend preparation plays an important role in the product quality, and mainly in traffic security. Because of its excellent corrosion resistance at elevated temperatures, cpvc is ideally suited for selfsupporting constructions where. Polymer materials are a kind of important materials that developed rapidly in biological applications. Low electrical and thermal conductivity, can be made conducting. A primary reason that polymer properties are different is because the chemical compositions of metals, polymers and ceramics are totally different. Each c atom has four ethat participate in bonds, each h atom has one bonding ehydrocarbon molecules i methane, ch4 ethane, c2h6 propane, c3h8. Some of these are discussed herewith in the following sections. Engineering properties of polyethylene introduction a fundamental understanding of material characteristics is an inherent part of the design process for any piping system. Mechanical properties of glass fiber reinforced polymers.
It is also readily workable, including machining, welding, and forming. Some of the useful properties of various engineering polymers are high strength or modulus to weight ratios light weight but comparatively stiff and strong, toughness, resilience, resistance to corrosion, lack of conductivity heat and electrical, color, transparency, processing, and low cost. Suhasini gururaja, ae, iisc bangalore 1 parts of the material for this presentation has been borrowed from lecture notes of prof. Plastics technology handbook plastics properties and testing. Our original sets of web components, built with the polymer library. High strength or modulus to weight ratios, toughness, resilience, resistance to corrosion, lack of conductivity heat and electrical, color, transparency are properties which are present in most of polymer materials. Mechanicalpropertiesof polymers harvard university. Remember that a real polyethylene molecule is more often 100 or atoms long. Properties are the observed characteristics of a sample.
For instance, polymer scientists in other fields have been able to. Since it has no functional groups, the skeleton structure of a polyethylene fragment looks like it does not have any atoms. Suhasini gururaja assistant professor aerospace engineering, iisc, bangalore overview of mechanical properties for pmcs dr. Mechanical performance of polymer systems materials technology. It highlights previous work done in bamboo fiber in terms of the reinforcement composite material.
T f w as evlu td co r ing iso527 mp tensile plot of unfilled victrex polymers is. Introduction to materials science chapter 19, thermal properties 8 thermal expansion materials expand when heated and contract when cooled t t t l l l l l l f l f. Physical properties of polymers a thermoplastic polymer is one that can be softened by heating and then formed into desired shapes by applying pressure. Thermoset is a polymer that is cured by heat or chemical reaction and becomes infusible and insoluble material.
For this reason, it has better moisture resistance, dimensional stability, and electrical properties, but the degree of crystallinity, the melting point and the mechanical properties are. Chemical properties of polymers the chemical properties of polymers are very similar to those of analogous small molecules. The higher is t, the large is the mean atomic velocity and the. Thermoset polymers posses a cross linked molecular structure and are formed in two stage polymerization. With such an understanding, the piping designer can use the properties of the material to design for optimum performance. Mechanicalpropertiesof polymers kamyardavoudi october,20 materials scienceseminar. The mechanical properties of a polymeric thermoset material are determined by several factors that are derived from the chemical structure such as the mobility of the polymer backbone, the degree of crystallinity, intermolecular forces, the crosslinking density, dangling chain. Pdf in this study, we studied the physical and mechanical properties of polymer composite with wastes that incorporating boron.
Another class of materials used in mst is composites, which are made of a combination of materials such as. Good strengthtoweight ratios for certain but not all polymers. These fibres are introduced to enhance selected properties of the material 2. Methods of recycling, properties and applications of recycled. These processes include impact damage, delamination, water absorption, chemical attack, and hightemperature creep.
Fiberglass is made by dispersing glass fibers in a polymer matrix. Therefore a hookean material is linear elastic, and materials engineers use these descriptors interchangeably. Find materials for this course in the pages linked along the left. The first stage is formation of a polymer with linear chains. Effect of temperature on the mechanical properties of polymer. Code 7 is used to designate miscellaneous types of plastic not defined by the other six codes. Thermosetting polymers become permanently hard at elevated temperatures and pressures. Mechanical properties, dynamic mechanical properties, stress, strain, polymer, plastics, elastomers, rubber contents 1.
Such a material iselastic accordingtothedescription ofelasticity given earlier immediate response,fullrecovery, andit is also linear in its relation between stress and strain or equivalently, force and deformation. Advanced materials by design constituents of polymer matrix composites matrix the matrix properties determine the resistance of the pmc to most of the degradative processes that eventually cause failure of the structure. Introduction to materials science, chapter 15, polymers. Also, you may want to use our plastic material selection guide or interactive thermoplastics triangle to assist with the material selection process based on your application requirements. The underlying objective of this discussion is to simply define. Chlorinated polyvinyl chloride cpvc properties cpvc shares most of the features and properties of its close relative, pvc. This page contains materials for the polymers class session on synthesis, properties and applications. Physical, thermal, and mechanical properties of polymers.
The first process involves large deformations and subseq uent relaxation of rubber domains, during which filler aggregates are sandwiched between rubber layers. Polymer materials, typical material classes, molecular and morphological structure of polymers, polymer blends and alloys testing methods of polymer structures mechanical behavior of polymer materials behavior of polymers under changing temperature, humidity and other environmental factors strength and fracturemechanical properties of polymers. Most polymers are organic, and formed from hydrocarbon molecules. Polymer materials and its properties jana i akova alexander dub ek university faculty of industrial technologies in puchov slovakia 1. Physical properties of polymers textile study center. Explain how crosslinking produces the characteristic properties of an elastomer. Abnormal plasticizing is companied by bad mechanical properties of. Bhowmick indian institute of technology, kharagpur, india keywords. The product is called polymer and the starting material is called monomer.
This method is able to transform the plastic material into smaller molecules, suitable for use as feedstock material starting with monomers, oligomers, or mixtures of other hydrocarbon compounds 36,38. Some of these are discussedherewithinthefollowingsections. The interest in polymer materials and its application rising, e. Mechanical and morphological properties of ligninbased. For chemically resistant plastic, view our chemical resistance of plastics chart. Polymers have many inherent properties that can be further enhanced by a wide range of additives to broaden their uses and applications. Modulus of rigidity shear modulus modulus of rigidity is the elasticity coefficient for shearing or torsion force. The tensile strength of a material quantifies how much elongating stress the material will endure before failure. Pdf superabsorbent polymer sap materials are hydrophilic networks that can absorb and retain huge amounts of water or aqueous solutions. The properties of interest for how well a polymer prints include melting. Strain stress mpa highly elastic elastomer ductile polymer semi crystalline polymer plastichigh temperature.
Silk fiber is produced by silk worms in a cocoon, to protect the silkworm while it metamorphoses into a moth framework of all plant life, as the main structure in cell wall the other main component in cell walls gelatin, wool, silk. A free online materials information resource with properties data on over 28,000 materials. Code 7 is used to designate miscellaneous types of. Different polymers with versatile properties are attractive because of their introduction and potential uses in many. A brief introduction to polymer material science is given in the following. The simplest definition of a polymer is a useful chemical made of many repeating units. Classification of engineering materials, and their properties. Cellulose, for example, is a polymer, but it cannot be processed like a plastic material unless it is modified. Since 1872 chemists have identified the common polymers produced by plants and animals, primarily proteins collagen, keratin and. If youre after basic information on plastic materials, this is the place to find it. Polymer composite an overview sciencedirect topics. Polymer can have different chemical structure, physical properties, mechanical behavior, thermal characteristics, etc. Describe a polymers structure in terms of mer type ordering, tacticity, and backbone chain configuration.
Comparison of ceramic and polymer building materials when the wolf huffed and puffed, the straw and stick houses fell down. The most powerful computers our brains are mostly just a complex polymer material soaking in salty water. It is less hydrophilic than nylons 6,6 and 6 due to the larger number of methylene groups in the polymer backbone. Numerous factors affect various mechanical properties of polymers, in cluding molecular weight, processing, extent and distribution of crystallinity, composition. Polymer matrix composites are materials made up of fibres that are embedded in an organic polymer matrix. Polymer macromolecules constructed by the repetition of primary monomer units in such a way that the properties of the material do. A brief introduction to polymer material science is given in the following subsections. Malleability, brittlenes and ductility plastic deformation properties. Bhowmick encyclopedia of life support systems eolss mechanical properties of polymers anil k. Ga sources and processing acacia senegal and acacia seyal trees are the main sources of ga. Material properties material properties for gases, fluids and solids densities, specific heats, viscosities and more. Biopolymers can be complex and nice introduction to materials science, chapter 15, polymer structures university tennessee, dept. Highdensity polyethylene hdpe consists primarily of. Fundamental information on the bulk properties of biomaterials basic level to enable understanding of metallic, polymeric, and ceramic substrates in the next few classes we will cover.
Polymer materials and its properties 19 in the initial stages of mixing before incorpor ation starts, two processes take place. Ht compounds showed slightly improved creep performance opposed to peek polymerbased equivalents. Characteristics, applications and properties of polymers. Mechanical properties and performance of materials samples of engineering materials are subjected to a wide variety of mechanical tests to measure their strength, elastic constants, and other material properties as well as their performance under a variety of actual use conditions and environments. There are over species of acacia and a summary of their botanical classification was reported by phillips and williams, 1993. Typical reactions for chain assembling are polyaddition continuous or step wise and condensation polymer ization polycondensation 1 figure 1.
Introduction engineers face several considerations when selecting the optimum polymer material for a product. Mechanical properties victrex materials are widely regarded as the highest performing thermoplastic polymers with good retention of mechanical properties over a wide range of temperatures and conditions. Polymers have many inherent properties that can be further enhanced by a wide range of additives to. It features a 1hour lecture video, and also presents the prerequisites, learning objectives, reading assignment, lecture slides, homework with solutions, and resources for further study. Polymer matrix composites are classified based on their level of strength and stiffness into two distinct types. Use our interactive properties table below to explore by property group, sort, or compare two or more plastic materials.
A structural engineer who wishes to use adhesives must understand at least the rudiments of polymer chemistry, in much the same way that a structural engineer working with metal alloys must understand at least the rudiments of metallurgy. A suite of polyfills supporting the web components specs. However, even at lower strain rates, conducting mechanical tests at small scalethat is, at the microstructural level, on the order of nanometers or micronswill likely shed light on. Here youll learn the definition and properties of polymers, another name for plastics. From the utility point of view they can be classified into three main categories. Physical properties of polymers include molecular weight, molar volume, density, degree of polymerization, crystallinity of material, and so on.
Plastic material properties table mechanical, physical. Polyaryletherketones paeks are a class of semicrystalline high performance engineering thermoplastics having a unique combination of thermal stability, chemical resistance, and excellent mechanical properties over a wide temperature range. It is possible to modify the properties of polymer materials by either adding stabilizer or plasticizers. A functional group attached to a polymer chain generally reacts the same way it would if present in a monomer. This document pdf may be used for research, teaching and private study purposes. The bulk properties of a polymer are those most often of enduse interest.
Chemists have also learned to synthesize new polymers from simple chemicals, creating a vast array of plastics and synthetic fibers. Polymers are composed of nonmetallic elements, found at the upper right corner of the periodic table. The resulted monomers can be used for new polymerizations to reproduce the original or a related polymeric product. Physical and mechanical properties of materials melting temperature 9 density 10 youngs modulus 11 yield stress and tensile strength 12 fracture toughness environmental resistance 14 uniaxial tensile response of selected metals and polymers 15 iii. These are the properties that dictate how the polymer actually behaves on a macroscopic scale. All plastics are polymers but not all polymers are plastics. Polymers a polymer is a macromolecule long molecules built of small covalently bonded units called monomers mer from the greek word meros meaning part. Synthetic polymer materials have many attractive properties, such as monodispersity, biocompatibility, controlled composition and chain length, and tunable chemical properties. A polymer composite is a multiphase material in which reinforcing fillers are integrated with a polymer matrix, resulting in synergistic mechanical properties that cannot be achieved from either component alone 1. The central idea of this chapter is structureproperty relationships, which means molecular characteristics such as molecular architecture, molecular weight, and chemical composition are directly related to the physical and chemical properties of the macroscopic material. Properties of polymers for fdm when choosing a thermoplastic polymer to use in afdm, there are many properties of polymers that can contribute to how well the part prints and the resulting properties of the printed parts. Other polymers can be foamed like polystyrene styrofoam, polyurethane and polyethylene. Synthetic polymers are humanmade polymers derived from petroleum oil. Database includes comprehensive coverage of thermoplastic and thermoset polymers, aluminum, cobalt, copper, lead, magnesium, nickel, steel, superalloys, titanium and zinc alloys, ceramics, plus a growing list of semiconductors, fibers, and other engineering.237 1022 186 426 233 1060 1383 376 1419 805 921 603 1379 1608 676 688 33 85 1050 1178 1470 806 173 336 599 804 499 404 398 1036 1249 1587 743 1019 189 557 751 864 641 90 727 411 739 17 36 431 248 919 1248 1181