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Reporter:Chen-Kun Lin
Adviser:Cheng-Chien Wang
2011.06.28
Introduction
• Epoxy resins have dimensional stability, satisfactory mechanical
properties, so that they are widely used as coating, adhesion,
lamination, casting and electronic encapsulation materials.
• However, the flammability of epoxy resins is a major problem in
applications where high thermal and flame resistance are needed.
• Many approaches have been used to improve the flame retardancy
of epoxy-resin composites.
Introduction
• A feasible way to reduce flammability of epoxy-resin composites
is the utilization of flame-retardant agents or fire-resistant curing
agents.
• Still commonly used are halogenated flame retardants, which
appear to function principally by reacting with radicals produced
during combustion (mainly H+ and OH-), generating less-reactive
halogen radicals.
• However, these reactions result in the release of toxic, corrosive,
halogenous gases, such as hydrogen chloride.
Introduction
• Consequently, low or zero use of halogen in flame retardants is the
current trend.
• Increasing use is being made of phosphorus-containing flame
retardants.
• The objective of this investigation is to reduce flammability of
epoxy-resin composites using an anhydride with a pendent
phosphorus and halogen-free group.
Materials
9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO)
Itaconic acid
Hexahydrophthalic anhydride (HHPA) and
phthalic anhydride (PA)
N-Benzyldimethylamine (BDMA)
Tetrahydrofuran and n-hexane
Experimental
Synthesis of (9 ,10 -dihydro -9 -oxa -10 -phosphaphenanthrene -10 -oxide )
methyl succinicanhydride (DMSA)
Experimental
Curing of epoxy networks
The samples
mixture was
werecontinuously
cured in a hot
stirred
pressand
at 130℃
then placed
for 3 hrinfollowed
an oven at
by 2
thepost-cure
hr
desired curing
at 170℃.
temperature (130℃).
Results and discussion
Monomer synthesis and characterizations
Results and discussion
Monomer synthesis and characterizations
Results and discussion
Thermal properties
Results and discussion
Thermal properties
Results and discussion
Thermal properties
Results and discussion
Flame properties
Results and discussion
Flame properties
Conclusions
• An aryl phosphinate anhydride (DMSA) was synthesizedby the
addition and dehydration reaction of DOPO with itaconic acid.
• The a major degradation of those epoxy-resin composites took
place in the same temperature range (350-450 ℃),and the initial
decomposition temperature was not significantly shifted.
• Epoxy resins cured with DMSA exhibit higher LOI values and
char yields compared with those cured by commercial curing
agents, such as PA and HHPA.
Conclusions
• Furthermore, the LOI value and the char yield of the epoxy-resin
composites increased with increasing phosphorus content.
• The utilization of appropriate amounts of DMSA in the epoxy
systems would give good flame retardancy.
回收NBR-BA微乳液聚合
0528-Size
0529-Size
0527EAc-Size
0527EAc
40
Number
30
20
10
0
0
200
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Size(nm)
1000
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1400
0529EAc-Size
0529EAc
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35
Number
30
25
20
15
10
5
0
0
100
200
Size(nm)
300
400
500
0611EAc-Size
FTIR
DOPO
Rubber
100
90
% Transmittance
80
70
60
50
40
30
20
10
4000
3500
3000
2500
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1500
-1
Wavenumbers/cm
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0624-FTIR
100
90
0hr
1hr
2hr
3hr
4hr
5hr
6hr
7hr
8hr
9hr
% Transmittance
80
70
60
50
40
30
20
4000
3500
3000
2500
2000
1500
-1
Wavenumbers/cm
1000
500