Polymerisation Processes Polymerisation Processes Polyethylene ...

PA6-process – modelling of solid state condensation
Model assumptions:
Polymer end groups, water,
monomer und oligomere only in
amorphous phase
reaction kinetics as in melt
diffusion coefficients dependent on
degree of crystallinity
surface is free of water
Isothermal spherical particle
Model output
Pn, monomer and oligomer
concentration
0 10 20 30 40 50
reaction tim e [h]
Dr. Klaus-Dieter Hungenberg, BASF AG Ludwigshafen Vorlesung Polymerisationstechnik, Universität Paderborn, WS 07/08 Polymer processes
Polyamide 66 - tank process
mass fraction of caprolactam [%]
number-average chain length
0.20
0.18
0.16
0.14
0.12
0.10
0.08
0.06
0.04
0.02
0.00
450
400
350
300
250
200
150
100
0 10 20 30 40 50
T = 125°C
T = 145°C
T = 165°C
T = 180°C
T = 190°C
model
reaction tim e [h]
T = 145°C
T = 165°C
T = 190°C
model
Dr. Klaus-Dieter Hungenberg, BASF AG Ludwigshafen Vorlesung Polymerisationstechnik, Universität Paderborn, WS 07/08 Polymer processes
81
83
PA66- basic reactions
O O
HO C (CH2 ) C
4
OH
Adipic acid Hexamethylene diamine
–H 2 O
Dr. Klaus-Dieter Hungenberg, BASF AG Ludwigshafen Vorlesung Polymerisationstechnik, Universität Paderborn, WS 07/08 Polymer processes
+
+ H 2 O
AH-salt solution
Polycondensation
O O
HO C (CH2 ) C
4
NH
NH
(CH 2 ) 6
H2N (CH CH2
) NH
6 2
Polyamide 66 – continous tubular process
H 2 O-Steam
tube reactor
Pump
Separator
40-60%
AH-Salt Solution
Devolatilisation
e.g. Extruder
Dr. Klaus-Dieter Hungenberg, BASF AG Ludwigshafen Vorlesung Polymerisationstechnik, Universität Paderborn, WS 07/08 Polymer processes
H
Pump
Polymer
Melt
Postcondensation
82
High energy consumption
Evt. loss of volatiles in
vapor
84