Polymers, both natural and synthetic, are created via polymerizationof many small molecul… ) depends on whether the polymer is above or below the onset of entanglements. The susceptibility of a polymer to degradation depends on its structure. Polymer molecules may combine up to million of monomers (mers) forming a one-dimensional structure (chain), two-dimensional structure (planar molecules) or three-dimensional structure. … Polymers are substances consisting of macromolecules and the high molecular weight and chain-like structure of the macromolecules are responsible for the unique properties of polymers. Dynamic mechanical analysis or DMA measures this complex modulus by oscillating the load and measuring the resulting strain as a function of time. Synthetic methods are generally divided into two categories, step-growth polymerization and chain polymerization. For the polymers mentioned here the (dn/dT) ~ −1.4 × 10−4 in units of K−1 in the 297 ≤ T ≤ 337 K range.[60]. Lipids help to store energy, cushion and protect organs, insulate the body, and form cell membranes. "plastics"). Cellulose, the main structural carbohydrate, is a polymer of glucose units linked together, forming a tough fiber. During the polymerization process, some chemical groups may be lost from each monomer. All polymers (amorphous or semi-crystalline) go through glass transitions. These features play a major role in determining the physical and chemical properties of a polymer. Introduction Introduction General Classifications Metals Ceramics Polymers Composites, Structure of Materials Atomic Bonds Solid State Structure Metallic Crystalline Structure Solidification Anisotropy and Isotropy Crystal Defects Elastic/Plastic Deformation Fatigue Crack Initiation Diffusion Property Modification Ceramic Structures Polymer Structure Composite Structures, Physical and Chemical Properties Phase Transformation Temp Density Specific Gravity Thermal Conductivity Thermal Expansion Electrical Conductivity Magnetic Properties Oxidation and Corrosion, Mechanical Properties -Loading -Stress & Strain Tensile Compression, Bearing, & Shear Hardness Creep & Stress Rupture Toughness -Impact Toughness -Notch Toughness -Fracture Toughness Fatigue -S-N Fatigue -Fatigue Crack Growth Rate, Selection of Materials Specific Metals Metal Ores Iron and Steel Decarburization Aluminum/Aluminum Alloys Nickel and Nickel Alloys Titanium and Titanium Alloys General Manufacturing Processes Metallic Components Ceramic and Glass Components Polymers/Plastic Components Composites, Manufacturing Defects Metals Polymers Composites, Service Induced Damage Metals Polymers Composites Material Specifications, Component Design, Performance and NDE Strength Durability Fracture Mechanics Nondestructive Evaluation. Polymers are composed of long molecular chains which form irregular, entangled coils in the melt. Semi-crystalline polymers can undergo crystallization and melting transitions, whereas amorphous polymers do not. PRIMARY STRUCTURE OF POLYMERS The main feature of the primary structure is the monomer composition and pattern (homopolyer, alternating, block, etc.) Degree of polymerization is an average number of monomers (mers) in a polymer molecule. Cross-links and branches are shown as red dots in the figures. They are classified as bulk properties, or intensive properties according to thermodynamics. Modern society would look very different without them. Structured Polymers is the world’s first colored ink manufacturer for industrial 3D printers that provides true color to the core. Young's modulus quantifies the elasticity of the polymer. hide. How do you determine the structure of the polymer? 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