how do we know that a given material is a polymer?
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Polymer is a generic term used to describe a very long molecule consisting of structural units and repeating units connected by covalent chemical bonds.  The key feature that distinguishes polymers from other molecules is the repetition of many identical, similar, or complementary molecular subunits in these chains. These subunits, the monomers, are small molecules of low to moderate molecular weight, and are linked to each other during a chemical reaction called polymerization.
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Not enough information provided. The density of any carbon fiber product is based apon the requirements of the product and its use. The amount of polymer to fiber ratio is based on that information.
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Molecular weight is the weight of a mole of a compound.  Polymers are different plastics that are made by chemical reactions.\n\nA understanding of this subject should allow you to calculate the density of different polymers or plastics among other things.
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All substances have properties that we can use to identify them. For example we can idenify a person by their face, their voice, height, finger prints, DNA etc.. The more of these properties that we can identify, the better we know the person. In a similar way matter has properties - and there are many of them. There are two basic types of properties that we can associate with matter. These properties are called Physical properties and Chemical properties:\n\nPhysical properties: Properties that do not change the chemical nature of matter \nChemical properties: Properties that do change tha chemical nature of matter\n\nExamples of physical properties are: color, smell, freezing point, boiling point, melting point, infra-red spectrum, attraction (paramagnetic) or repulsion (diamagnetic) to magnets, opacity, viscosity and density. There are many more examples. Note that measuring each of these properties will not alter the basic nature of the substance.\n\nExamples of chemical properties are: heat of combustion, reactivity with water, PH, and electromotive force.\n\nThe more properties we can identify for a substance, the better we know the nature of that substance. These properties can then help us model the substance and thus understand how this substance will behave under various conditions.
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A thermoplastic is a material that is plastic or deformable, melts to a liquid when heated, and freezes to a brittle, glassy state when cooled sufficiently. Most thermoplastics are high molecular weight polymers whose chains associate through weak van der Waals forces (polyethylene); stronger dipole-dipole interactions and hydrogen bonding (nylon); or even stacking of aromatic rings (polystyrene). Thermoplastic polymers are contrasted with thermosetting polymers (Bakelite; vulcanized rubber), which, once formed and cured, can never be remelted and remolded. Many thermoplastic materials are addition polymers; e.g., vinyl chain-growth polymers, such as polyethylene and polypropylene.
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Polyester is a category of polymers which contain the ester group in its' main chain. \n\nUsually, polyester refers to cloth woven from polyester fiber. \n\nPolyesters do exist in nature (Plant Cuticle), however, polyester generally refers to the large family of synthetic polyesters (plastics) which includes polycarbonate and polyethylene terephthalate (PET).\n\nGet an "A".
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lots of materials' properties can be found. you can try this link..
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Yes, all of these are polymers.  While appearing to be different, they are all long chain molecules or polymers.  They all fit into the subset linear polymers, or chain molecules that have no branching points.
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ref\n\nhttp://www.cem.msu.edu/~reusch/VirtualText/polymers.htm
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Well, look in the periodic table of the elements and find the molecular weight. The molecular weight tells you how many grams are in one mole of that element. Once you know the amount of grams that correspond to 1 mole, you do the math.\nGood luck!
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If you know the density of the material, you can measure it's volume.  D = M / V.  Therefore, the mass equals the density of the object times the volume.  The weight of the material is its mass times gravity.
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Plastic state.  \n:-) Hope this helps!
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Polymers are made when you have a single unit -- a monomer -- that can react with other units to form a long chain.  As such, an alkane such as methane or ethane cannot form a polymer, since there is no way for them to polymerize.\n\nHowever, and alkEne, such as ethylene -- with a chemical structure H2C=CH2 -- can polymerize, becuase the double bond can be broken and add two more monomers to start forming the chain.  This is how polyethylene is made.  The double bond can also participate in cross-linking with other chains, which alters the properties of the polymer.\n\nPolyesters are the result of the reaction of a di-carboxylic acid with a glycol.  Carbohydrate monomers can link up to form dimers, trimers, and longer polymers that create the backbones of many living systems.  Polyisoprene is the name for natural rubber -- another polymer.\n\nPolymer science is a huge, and growing subset of chemistry.
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nylon\n\nmade from petro chemical
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We, along with everything else in the world, are made up of atoms. Atoms are the basic building block of all matter.  The periodic table lists the different "elements" in the universe. Each element is made of a unique kind of atom, and there are no other kinds. For example, you can have oxygen atoms, or carbon atoms, but there are no plastic atoms. Anything more complex than the elements is made by sticking atoms together to form molecules - you *can* have a plastic molecule.\n\nAtoms consist of a nucleus, which contains protons (positively charged particles) and neutrons (no electrical charge.) The protons and neutrons are the heavy part of an atom. Electrons (negatively charged particles) orbit around the nucleus. \n\nThere are always the same number of protons and electrons, so the positive and negative charge cancel each other out. The number of neutrons can vary. Adding the number of protons and neutrons will give you the "atomic mass" of an element.
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u should instead study the properties of different types of compounds like metals, covalent compounds, ionic, macromolecular. then go on to the types of bonds which will explain their physical properties. then apply what u learn to any compund u come across.
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DSC can be used to measure the extent of reaction in a polymerization reaction (epoxy resin reacting with diamine hardeners, for instance).  At room temperature such a reaction will likely not go to completion as the three dimensional molecule forming "locks up" as it progresses from the liquid into the solid phase.  A DSC can measure the amount of exothermic energy still available in a sample of plastic and, thus, determine how far the reaction went at room temperature.\n\nAll plastics have a point in a modulus vs. temperature curve where the modulus changes most rapidly with the least increase in temperature.  This is known as the Glass Transition Temperature (Tg).  It can be thought of as the point where a plastic behaves more as a rubber like material versus a glass like material at a lower temperature.  A DSC can also measure this.