--%>
Assignment Help - homework help

What are various structure based polymers?

This classification of polymers is based upon how the monomeric units are linked together. Based on their structure, the polymers are classified as:


1. Linear polymers: these are the polymers in which monomeric units are linked together to form long straight chains. The polymeric chains are stacked over one another to give a well packed structure. As a result of close packing, such polymers have densities, high tensile strength and high melting points. Common examples of such type of polymers are polyethylene, nylons and polyesters.

2. Branched chain polymers: in this type of polymers, the monomeric units are linked to constitute, long chains (called the main-chain). There are side chains of varied lengths which comprise branches. Branched chain polymers are irregularly packed and thus, they have low density, lower tensile strength and lower melting points as compared to linear polymers. Amylopectin and glycogen are common examples of this type.

3. Network polymers or Cross-linked: in this type of polymers, the monomeric units are linked together to constitute a three-dimensional network. The links involved are called cross-links. Cross-linked polymers are hard, rigid and brittle because of their network structure. Common examples of this type of polymers are Bakelite, melamine formaldehyde resin, etc.

 

 

   Related Questions in Chemistry

  • Q : Explain Ionic Bond with examples. The

    The bonding in ionic molecules can be described with a coulombic attractive term.For some diatomic molecules we take quite a different approach from that used in preceding sections to describe the bonding. Ionic bonds are interpreted in terms of the coulom

    		•
  • Q : M ive me answer of this question. When

    ive me answer of this question. When mercuric iodide is added to the aqueous solution of potassium iodide, the: (a) Freezing point is raised (b) Freezing point is lowered (c) Freezing point does not change (d) Boiling point does not change

    		•
  • Q : Finding Molarity of final mixture Can

    Can someone help me in finding out the right answer. 25ml of 3.0 MHNO3 are mixed with 75ml of 4.0 MHNO3. If the volumes are adding up the molarnity of the final mixture would be: (a) 3.25M (b) 4.0M (c) 3.75M (d) 3.50M

    		•
  • Q : Thermodynamics I) Sulphur dioxide (SO2)

    I) Sulphur dioxide (SO2) with a volumetric flow rate 5000cm3/s at 1 bar and 1000C is mixed with a second SO2 stream flowing at 2500cm3/s at 2 bar and 200C. The process occurs at steady state. You may assume ideal gas behaviour. For SO2 take the heat capacity at constant pressure to be CP/R = 3.267

    		•
  • Q : Molarity of Nacl solution When 5.85 g

    When 5.85 g of NaCl (having molecular weight 58.5) is dissolved in water and the solution is prepared to 0.5 litres, the molarity of the solution is: (i) 0.2 (ii) 0.4 (iii) 1.0 (iv) 0.1

    		•
  • Q : Influence of temperature Can someone

    Can someone please help me in getting through this problem. With increase of temperature, which of the following changes: (i) Molality (ii) Weight fraction of solute (iii) Fraction of solute present in water (iv) Mole fraction.

    		•
  • Q : What are Vander Waal's Radii? Vander

    Vander Waal's radii can be assigned to the atoms of molecules on the basis of the closeness of approach of these atoms in crystalline substances. Diffraction studies of crystals give information about hoe molecules can approach each other and can pack

    		•
  • Q : Describe the properties of the

    Briefly describe the properties of the carbohydrates?

    		•
  • Q : Problem on relative humidity Relative

    Relative humidity is the ratio of the partial pressure of water in air to the partial pressure of water in air saturated with water at the same temperature, stated as a percentage: Relative  =

    Q : How can enzymes act as catalyst?

    Enzymes are complex proteinous substances, produced by living bodies, such as act as catalysis in the physiological reactions. The enzymes are, also called biochemical catalysts and the phenomenon is known as bio-chemical catalysis because numerous reactions that occur the bodies of animals and p

    		•