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Polyvinylidene fluoride (PVdF) is a thermoplastic polymer whose repetitive unit

ID: 574834 • Letter: P

Question

Polyvinylidene fluoride (PVdF) is a thermoplastic polymer whose repetitive unit is shown in the following figure H F Repetitive unit of polyvinylidene fluorid We have the following information: Morphology: Glass transition temperature Melting temperature a) If the molar mass (Mpoy) of this polymer is 352.2kg / mol, what is its degree of Semi-crystalline -35°C 160°C polymerization "n"] b) Which fluorine mass is contained in 0.450 mol of this polymer (in kg)? c) At 200 degrees Celsius, which term best describes the mechanical behavior of this polymer: glassy, viscoelastic or rubbery?

Explanation / Answer

a) Molar mass of polymer = 352.2 kg/mol

Molar mass of monomer (vinyledene fluoride) = 64 g/mol = 0.064 kg/mol

Degree of polymerisation = molar mass of polymer/molar mass of monomer = 352.2/0.064 = 5503.1

b) degree of polymerisation = 5503.1

So, 1 mole of polymer contains 5503.1 monomers

0.450 mol of polymer will contain = 0.450*5503.1 = 2476.4 monomers

1 monomer has 2 fluorine atoms

atomic mass of fluorine = 19 g/mol

mass of fluorine in 1 monomer = 2*19 = 38 g

mass of flurine in0.450 mol of polymer = 38*2476.4 = 94103 g = 94.103 kg

c) Melting point of polymer is 160 oC. The polymer is semi-crysatlline

At 200 oC, the polymer will be in viscoelastic in nature.

If the polymer had been amorphous, then it would be rubbery above melting point.

Below glass transition temperature, the polymer is glassy.