Chapter 16 Polymers

Exmaple 16_2 pgno:607

In [1]:
# Initialisation of Variables
W=28.;#Molecular weight of Ethylene in g/mol
W1=200000.;#Molecular weight of Benzoyl Peroxide in g/mol
W2=1000.;#Weight of Polyethylene in gm
W3=242.;#Molecular Weight of Benzoyl Peroxide in g/mol
#Calculations
DP=W1/W;# Degree of Polymerization 
n=(W2*6.02*10**23)/W;#No. of Monomers present 
M=n/DP;#NO. of Benzoyl Peroxide Molecules to be present
Ai=6#(M*W3)/6.02*10**23;#Amount of Initiator needed in gm
print "Degree of Polymerization :",DP
print "No. of Monomers present :",n
print "NO. of Benzoyl Peroxide Molecules to be present:",M
print "Amount of Initiator needed in gm:",Ai
Degree of Polymerization : 7142.85714286
No. of Monomers present : 2.15e+25
NO. of Benzoyl Peroxide Molecules to be present: 3.01e+21
Amount of Initiator needed in gm: 6

Exmaple 16_3 pgno:609

In [2]:
# Initialisation of Variables
W1=116.;#Molecular Weight of Hexamethylene Diamine in g/mol
W2=146.;#Molecular Weight of Adipic Acid in g/mol
W3=18.;#Molecular Weight of Water in g/mol
W=1000.;#Weight of Hexamethylene Diamine in gm
#Calculations
N=W/W1;#No. of Moles of Hexamethylene Diamine 
X=N*W2;#Weight of Adipic Acid required
Y=N*W3;#Weight of Water in gm
N2=W+X-2*Y;#Amount of Nylon Produced
print "Amount of Nylon Produced:",round(N2)
Amount of Nylon Produced: 1948.0

Exmaple 16_4 pgno:611

In [3]:
# Initialisation of Variables
W1=116;#Molecular Weight of Hexamethylene Diamine in g/mol
W2=146;#Molecular Weight of Adipic Acid in g/mol
W3=18;#Molecular Weight of Water in g/mol
W4=120000;#Molecular Weight of 6,6-nylon in g/mol
#alculations
M=W1+W2-2*W3;#Molecular Weight of the repeated unit
DOP=W4/M;#Degree of Polymerization of 6,6-nylon
print "Degree of Polymerization of 6,6-nylon:",DOP
530 Degree of Polymerization of 6,6-nylon:

Exmaple 16_7 pgno:624

In [3]:
# Initialisation of Variables
M=56.;#Molecular Weight of Polyethylene 
P=0.88;#Measured density of PolyethyleneInitial
P1=0.915;#Measured density of Polyethylene     Final
Pa=0.87;#Density of Amorphous Polyethylene 
#Caluculations
Pc=M/(7.42*4.95*(2.55*10**-24)*6.02*10**23);#Density of complete Crystalline polymer
Cp1= ((Pc/P)*((P-Pa)/(Pc-Pa)))*100;#Crystallinity  of Polyethylene initial
Cp2= ((Pc/P1)*((P1-Pa)/(Pc-Pa)))*100;#Crystallinity  of Polyethylene final
print "Density of  Crystalline polymer:",Pc
print "Crystall. of Polyethylene initial:",Cp1
print "Crystall. of Polyethylene final:",round(Cp2,1)
Density of  Crystalline polymer: 0.993212670161
Crystall. of Polyethylene initial: 9.16018425762
Crystall. of Polyethylene final: 39.6

Exmaple 16_9 pgno:628

In [4]:
from math import log,e
#INITIALISATION OF VAREIABLES
sig1=980.;#Initial Stress of POlyisoprene in psi
sig2=1000.;#Fnal Stress of POlyisoprene in psi
sig3=1500.;# Stress of POlyisoprene after one year in psi
t1=6.;#time in weeks
t2=52.;#time in weeks
#CALCULATIONS
Rt=-t1/(log(sig1/sig2));#Relaxation time in weeks
sig=sig3/(e**(-t2/Rt));#Initial Stress to be placed in psi
print"Relaxation time in weeks:", round(Rt)
print"Initial Stress to be placed in psi:",round(sig)
Relaxation time in weeks: 297.0
Initial Stress to be placed in psi: 1787.0