Java程序辅导

Ageing of Skinned Polyethylene Pipe by Outdoor Exposure        
Researcher: Jian Huang
Project Duration: 2006-2009
Supervisors: Prof. Marianne Gilbert 
Abstract ProFuse HDPE pipe is produced with a polypropylene skin to improve socket electro-fusion joint integrity. The skinned HDPE pipe is being
investigated in this project in order to find out the protection provided by the polypropylene skin to the core pipe during outdoor aging and pressure
ResultsExperimental
testing. It is found that the polypropylene skin gives protection against oxidation and quenching during processing. Further experiments will be carried
out on weathered ProFuse to investigate how the skin protects the core pipe during outdoor aging, and affects its properties during pressure testing.
Crystallinity summaryDensity Profile Along Thickness
PP skin
70.91
70.37
70.74
70.93
71.13
69 80
70.00
70.20
70.40
70.60
70.80
71.00
71.20
c
r
y
s
t
a
l
l
i
n
i
t
y
 
b
y
 
w
e
i
g
h
t
/
%
    
0.9505
0.9515
0.9525
0.9535
 
(
g
/
m
l
)
Outdoor weathering  test in Arizona
HDPE core pipe
.
BPP NSPF 0.4SPF 0.8SPF 1.5SPF
Sample name 
OT surface free energy summary
4 2 . 5 9
3 5 . 4
20
30
40
50
c
e
 
f
r
e
e
 
y
(
m
N
/
m
)
0.9455
0.9465
0.9475
0.9485
0.9495
1 2 3 4 5 6 7 8 9 10 11
D
e
n
s
i
t
y
Decreased 
quenching 
effect
ProFuse pipe  
The background should remain white
Pressure test 
1 2 . 2 0 9 . 7 6 1 1 . 3 5
0
10
BPP No skin 0.4mm skin 0.8mm skin 1.5mm skin
s
u
r
f
a
c
e
n
e
r
g
y
OT Carbonyl index summary
0.26
0.25
0.30
1
4
7
2
)
Distance along thickness from inside to outside (mm) 
BPP NSPF 0.4SPF 0.8SPF 1.5SPF
Density distribution along thickness shows  an 
insulation effect of skin on core pipe during 
processing, which results in a higher bulk 
crystallinity. 
-0.6
-0.4
-0.2
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
A
b
s
 0.4mmPFexternal
 0.4mmPFmiddle
Sponsors
0.19
0.11
0.17 0.17
0.00
0.05
0.10
0.15
0.20
BPP NSPF 0.4SPF 0.8SPF 1.5SPF
C
a
r
b
o
n
y
l
 
i
n
d
e
x
(
A
1
7
4
3
/
A
1
Contact angle and ATR-FTIR results show a 
lower oxidation value which indicates that skin 
protects the polyethylene outer surface against 
oxidation during processing.  
5000 4500 4000 3500 3000 2500 2000 1500 1000 500
Wave numbers(cm-1)
ATR-FTIR characterization 
materials@lboro
Special thanks to EPSRC, Department studentship and Uponor
Co. Ltd, UK for their financial support.
Density Gradient Column Contact Angle Oxidation induction time test