Polymers

Question 1

_______ are engineering materials of very high molecular weight
 Created by joining together single units called ________ to make a single large monomer
molecule
 One of the common examples of polymers is ________, composed of repeating ethylene
molecules (C2H4)
 extensively used in food packaging, clothing, home furnishing, transportation, medical
devices, information technology, and other multifarious applications
 Natural polymers: silk, wool and cotton

Answer 1

Polymers
monomer
polyethylene

Question 2

___________ is a chemical reaction in which monomer units combine to form larger
molecules that contain repeating structural units

Answer 2

Polymerization

Question 3

Types of Polymerization

Answer 3

a. Chain-reaction Polymerization or Addition Polymerization
b. Step-Reaction Polymerization or Condensation Polymerization

Question 4

monomers simply add to one another to form the polymer.
 Examples of this are LDPE, HDPE, PVC, PP, and PS

Answer 4

Chain-reaction Polymerization or Addition Polymerization

Question 5

 Two monomers add in a condensation reaction under the release of water or another small
molecule like hydrogen chloride
 Examples of this are PET, PU and PA

Answer 5

Step-Reaction Polymerization or Condensation Polymerization

Question 6

Polymer may have similar molecular weights, but can have different properties, which mainly depends
on the __________

 Branching can be distinguished by ______ of the polymer
 ____________ is resulted when highly linear polyethylene molecules can be
closely packed
 ______________ are highly branched molecular chains which cannot be packed
closely together
 ____________ (LLDPE) which has short controlled side branches

Answer 6

degree of branching
density
High-density polyethylene (HDPE)
Low-density polyethylene (LDPE)
Linear-low density polyethylene

Question 7

Polymer Linking

__________ made by linking only one type of small molecule or monomer

__________
two different types of monomers are joined in the same polymer chain

________
Three different types of polymer are joined in one polymer chain

Purpose of copolymerization:
combine properties of different monomers to enhance and improve the
property of the final product or material

Answer 7

Homopolymer

Copolymer

Terpolymer

Question 8

_________ is the way in which atoms bond with each other.
 one of the atoms exerts a stronger attractive force on the electrons in the bond, resulting to ________
sharing of electrons
A polymer is polar if it has _______ and negative poles. If non, then it is ______.

Answer 8

Polarity
unequal
positive
nonpolar

Question 9

Polarity and Material Properties
________ influences material properties such
as:
1. Melting point
2. Solubility
3. Barrier
4. Coefficient of Friction of Stickiness
Factors Affecting Polymer Properties
1. Elemental Composition
2. Polarity
3. Size or Molecular Weight
4. Shape of Molecule
5. Thermal History
6. Mechanical History

Answer 9

Polarity

Question 9

MOLECULAR STRUCTURE AND PROPERTIES

1. Crystallinity
    Highly ordered molecular arrangements -“________”
    Completely random arrangements - “______’

 A polymer with lower crystallinity will have better ____

2. Molecular Weight Distribution
    Polymers don’t have a __________
    The greater the molecular weight distribution, the __________.
3. ________
    materials exhibiting both viscous and elastic characteristics
    also known as anelasticity, which is present in systems when undergoing deformation.
    Accordingly, rapid application of a load to plastic will cause it to _____, and will return to its
   original shape once the load is released.

Answer 9

crystalline
amorphous

clarity

specific molecular weight

easier to melt the plastic

Viscoelasticity

bend