Tag: polymer

Quizzes (7) Questions (194)

Questions Related to polymer

Multiple choice chemistry polymer addition polymerisation types of polymerisation reactions petrochemicals and polymers

Which of the following polymers can be made by free radical addition polymerisation mechanism?

  1. PE

  2. HDPE

  3. LDPE

  4. Telfon
Reveal answer Fill a bubble to check yourself
A,B,C,D Correct answer
Explanation

The polymers polyethene (PE), low density polyethene(LDPE), high density polyethene(HDPE) and teflon (polytetrafluoroethylene) can be made by free radical addition polymerisation (also known as chain growth polymerisation) mechanism.  To obtain free radicals, initiators such as benzoyl peroxide, tert-butyl peroxide or acetyl peroxide are used.

Multiple choice chemistry polymer addition polymerisation types of polymerisation reactions petrochemicals and polymers

$\begin{bmatrix}-CH _2-\underset{\underset{\textstyle\;OH}{\displaystyle\mid}}{\;\;\;CH}-CH _2-\underset{\underset{\textstyle\;OH}{\displaystyle\mid}}{\;\;\;CH}-CH _2-\underset{\underset{\textstyle\;OH}{\displaystyle\mid}}{\;\;\;CH}-\end{bmatrix} _n$

Polyvinyl alcohol (as shown above) is a unique polymer having high affinity for water. Which of the following procedures would be most suitable for its preparation?

  1. radical chain polymerisation of $CH _2=CH-CH _2-OH$
  2. radical chain polymerisation of $CH _2=CH-OH$
  3. radical chain polymerisation of $CH _2=CH-CO _2CH _3$, following by base catalysed hydrolysis
  4. radical chain polymerisation of $CH _2=CH-OCOCH _3$, followed by acid catalysed hydrolysis
  5. radical chain polymerisation of $CH _2=CH-OCOCH _3$, followed by base catalysed hydrolysis
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

$\begin{bmatrix}-CH _2-\underset{\underset{\textstyle\;OH}{\displaystyle\mid}}{\;\;\;CH}-CH _2-\underset{\underset{\textstyle\;OH}{\displaystyle\mid}}{\;\;\;CH}-CH _2-\underset{\underset{\textstyle\;OH}{\displaystyle\mid}}{\;\;\;CH}-\end{bmatrix} _n$ 


Polyvinyl alcohol is prepared by radical chain polymerisation of  $CH _2=CH-OCOCH _3$, followed by base catalysed hydrolysis in which acetate group is replaced by hydroxide group. 

Multiple choice chemistry petrochemicals and polymers addition polymerisation types of polymerisation reactions polymer

Polystyrene is an example of ___.

  1. elastomer

  2. fibre

  3. cation polymerisation polymer

  4. thermosetting polymer
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

ELASTOMER  -  $Elastomers$ are rubber-like solids with elastic properties.
FIBRE  -  Fibre polymers are the thread forming solids with high tensile strength and high modulus.
THERMOSETTING  POLYMER  - These polymers are cross-linked or heavily branched molecules, which on heating undergo extensive cross-linking in moulds and again become infusible.
POLYSTYRENE - $Polystyrene$ is a thermoplastic polymer. It is formed by cation polymerisation. Hence, it is an example of a $cation$ $polymerisation$ $polymer$.

Multiple choice chemistry petrochemicals and polymers addition polymerisation types of polymerisation reactions polymer

The polymer used for post operative stitches is:

  1. glycolic acid

  2. poly lactic acid
  3. Nylon -$2$ - Nylon - $6$

  4. PHBV
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Polylactic acid is a thermoplastic aliphatic polyester derived from renewable resources
Polylactic acid is used for post operative stitches as it breaks down inside the body within $6$ months to $2$ years.

Multiple choice chemistry petrochemicals and polymers addition polymerisation types of polymerisation reactions polymer

Nylon-6, 10 is a polymer of :

  1. hexamethylene and adipic acid

  2. hexamethylene and sebacic acid

  3. caprolactam

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Nylon-6,10 is a copolymer synthesized through the condensation reaction of hexamethylenediamine (which contains 6 carbon atoms) and sebacic acid (a dicarboxylic acid containing 10 carbon atoms). Adipic acid is used in the synthesis of Nylon-6,6 instead. Therefore, hexamethylene and sebacic acid are the correct reactants.

Multiple choice chemistry petrochemicals and polymers addition polymerisation types of polymerisation reactions polymer

Which polymer describes tail - to - tail addition? 

  1. $-CH _2-\underset{X}{\underset{|}{CH}}-CH _2-\underset{CH}{\underset{|}{X}}-$
  2. $-\underset{X}{\underset{|}{CH}}-CH _2-CH _2-\underset{X}{\underset{|}{CH}}-$
  3. $-CH _2-\underset{X}{\underset{|}{CH}}-\underset{X}{\underset{|}{CH}}-CH _2-$

  4. All of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
In tail to tail polymerization, $-X$ is located such that it is separated by $H$ atoms.

i.e, $-\underset { | }{ CH } -{ CH } _{ 2 }-{ CH } _{ 2 }-\underset { | }{ CH } -$
          $X$                                    $X$
Multiple choice chemistry petrochemicals and polymers addition polymerisation types of polymerisation reactions polymer

Which statement about poly(chloroethene) is correct?

  1. The polymer can be cracked to produce chlorinated alkenes

  2. The polymer has harmless combustion products

  3. The polymer is readily biodegradable when buried
  4. The repeat unit of the polymer has an $M _r$ of $97$.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Polychloroethene is an addition polymer. Chloroethene can polymerise to form poly(chloroethene). Hence they can be cracked to produce chlorinated alkenes.