[DECRIPTION]
Invention Title]
METHOD FOR PREPARING ESTER PLASTICIZER AND ESTER
PLASTICIZER PREPARED BY THE SAME
5
[Technical Field]
The present invention relates to a method for
preparing an ester plasticizer and an ester plasticizer
prepared by the method. More specifically, the present
10 invention relates to a novel method for preparing an ester
plasticizer and an ester plasticizer with improved
I physical properties prepared by the method.
15 An ester plasticizer is generally produced through an
esterification reaction of an acid with an alcohol. The I
esterification reaction is commonly performed in the I
presence of an acid or metal catalyst.
Di-2-ethylhexyl phthalate is commonly used as an ester
20 plasticizer, but it is harmful to humans. since it is an I
environmental hormone disturbing endocrine systems, and has -
limitations to improvement in processability and foamability
of resins. I
Accordingly, there is an urgent need for an ester
25 plasticizer which is eco-friendly and sufficiently improves
processability and foamability of resins, and a method for
effectively preparing the same.
[~iaclasurel
5 [~echnical problem]
Therefore, the present invention has been made in
view of the above problems, and it is an object of the
present invention to provide a novel method for'preparing
an ester plasticizer and an ester plasticizer with improved
10 physical properties prepared by the method.
The object of the present invention and other objects
will be accomplished by the disclosure given below.
[~echnical solution]
In accordance with one aspect of the present
invention, the above and other objects can be accomplished
by the provision of a method for preparing an ester
plasticizer comprising trans-esterifying 100 parts by
weight of dioctyl terephthalate with 0.1 to 89.9 parts by
20 weight of butyl alcohol.
In accordance with another aspect of the present
invention, provided is a method for preparing an ester
plasticizer including a) trans-esterifying 100 parts by
weight of dioctyl terephthalate with 0.1 to 89.9 parts by
25 weight of butyl alcohol, and b) removing unreacted butyl
alcohol and octyl alcohol as a reaction by-product by
combination distillation.
In accordance with another aspect of the present
invention, provided is an ester plasti-cix e r inc.11-].ding3 0
to 99% by weight of dioctyl terephthalate (DOTP), 1 to 70%
by weight of butyl octyl terephthalate (BOTP), and 0 to
20% by weight of dibutyl terephthalate (DBTP).
In accordance with another aspect of the present
invention, provided is a resin composition including the
10 ester plasticizer, and a vinyl resin or a vinyl chloride
resin.
[~dvantageous ~ffectsl
As can be seen from the afore-going, the present
15 invention is effective in providing a novel method for
preparing an ester plasticizer and an ester plasticizer
with superior physical properties prepared by the method.
[~rief Description of The ~rawingsl
FIG. 1 is a graph showing variation in amount of
butyl octyl terephthalate produced according to reaction
temperature control and presence of catalyst upon transesterification
reaction (amount of added butanol: amount
corresponding to 10% by weight of dioctyl terephthalate)
25 according to the present invention; and
FIG. 2 is a graph showing variation in amount of
butyl octyl terephthalate produced according to butanol
amount upon the trans-esterification reaction (reaction at
160"~) accordinq to the present invention.
[~est ~odel
Hereinatter, the present invention will be described
in detail.
The method for preparing an ester plasticizer
10 according to the present invention comprises transesterifying
100 parts by weight of dioctyl terephthalate
with 0.1 to 89.9 parts by weight of butyl alcohol.
The ester plasticizer means an ester compound which
is used or can be used as a plasticizer, a composition
15 consisting of such ester compounds, or a composition
comprising the ester compound or the ester compounds.
For example, through the trans-esterification
reaction, the dioctyl terephthalate is converted into 30
20 to 99% by weight of the dioctyl terephthalate, 1 to 70% by
weight of butyl octyl terephthalate, and 0 to 20% by
weight of dibutyl terephthalate. Within this range, there
is an effect of obtaining an ester plasticizer which
exhibits excellent process efficiency, superior
25 processability and high absorption rate.
In another example, through the trans-esterification
.' reaction, the dioctyl terephthalate is converted into 3.9
to 80% by weight of the dioctyl terephthalate, 10 to 60%
by weight of butyl octyl terephthalate, and 1 t.o 15% .by
5 weight of dibutyl terephthalate. Within this range, there
is an effect of obtaining an ester plasticizer which
- - -- - - - - - -
ex&ibitsP excellentP process efficiency, superior
processability and high absorption rate.
In another example, through the trans-esterification
. .
reaction, the dioctyl terephthalate is converted into 47
to 70% by weight of the dioctyl terephthalate, 20 to 50%
by weight of butyl octyl terephthalate, and 3 to 10% by
weight of dibutyl terephthalate. Within this range, there
is an effect of obtaining an ester plasticizer which
15 exhibits excellent process efficiency, superior
processability and high absorption rate.
In another example, through the trans-esterification
reaction, the dioctyl terephthalate is converted into 64.5
to 98.9% by weight of dioctyl terephthalate, 1 to 32% by
20 weight of butyl octyl terephthalate, and 0.1 to 3.5% by
weight of dibutyl terephthalate. Within this range, there
is an effect of obtaining an ester plasticizer which
exhibits excellent ' process efficiency, superior
processability and high absorption rate.
The butyl alcohol may be added in an amount of 0.1 to
Y 89.9 parts by weight, or 3 to 50 parts by weight, based on
100 parts by weight of the dioctyx terephthalate. Within
this range, there is an effect of obtaining an ester
plasticizer which exhibits excellent. process efficiency
5 and much improved processability and foamability.
A molar ratio of the dioctyl terephthalate to the
butyl alcohol is for example 1:0.005 to 1:5.0, 1:0.2 to
1:2.5, or 1:0.3 to 1:0.8. Within this range, there is an
effect of obtaining an ester plasticizer which exhibits
10 excellent process efficiency and much improved
processability and foamability.
The trans-esterification reaction is for example
performed at 120"~ t o 1 9 0 " ~1~35 °C to 180°c, or 141"~t o
179°C. Within this range, an ester plasticizer with a
15 desired compositional ratio can be obtained within a short
time .
A reaction time of the trans-esterification reaction
is for example 0.1 to 10 hours, 0.5 to 8 hours or 1 to 6
hours. Within this range, there is an effect of
20 economically obtaining an ester plasticizer with a desired
compositional ratio.
The reaction time of the present invention is
calculated from a time at which reactants are elevated in
temperature and then reach a reaction temperature.
The trans-esterification reaction may be for example
performed in the presence of an acid catalyst or a metal
catalyst. This is effective in reducing reaction time.
The acid catalyst is for example sulfuric acid,
methanesulfonic acid or p-to1uenesu1fon.i.c i d 8nd the
5 metal catalyst is for example an organometallic catalyst,
a metal oxide catalyst, a metal salt catalyst or a metal.
The metal component is for example tin, titanium,
zirconium or the like.
In addition, the trans-esterification reaction is for
10 example a non-catalytic reaction.
For example, the method for preparing . an ester
plasticizer may further include removing unreacted butyl
alcohol and octyl alcohol as a reaction by-product by
distillation, after the trans-esterification reaction.
The distillation is for example two-step distillation
for independently separating the- butanol and the octyl
alcohol from each pther using a difference in boiling
point.
In another example, 'the distillation may be
20 combination distillation. In this case, there is little.
compositional change of the and there is thus
an effect of relatively stably securing a desired ester
plasticizer composition.
The combination distillation means that butanol and
25 octyl alcohol are simultaneously distillated.
The ester plasticizer comprises 30 to 99% by weight
of dioctyl terephthalate, 1 to 70% by weight of butyl
octyl terephthalate, and 0 to 20% by weight of dibutyl
terephthalate. Within this range, improvement ef fect.s nf
processability and absorption rate of resins are
excellent.
'I'he ester plasticizer for example comprises 39 to 80%
by weight of dioctyl terephthalate, 10 to 60% by weight of
butyl octyl terephthalate, and 1 to 15% by weight of
dibutyl terephthalate. Within this range, processability
and absorption rate of resins are excellent.
In another example, the ester plasticizer comprises
47 to 70% by weight of dioctyl terephthalate, 20 to 50% by
weight of butyl octyl terephthalate, and 3 to 10% by
weight of dibutyl terephthalate. Within this range,
processability and absorption rate of resins are
excellent.
In another example, the ester plasticizer comprises
64.5 to 98.9% by weight of dioctyl terephthalate, 1 to 32%
by weight of butyl octyl terephthalate, and 0.1 to 3.5% by
weight of dibutyl terephthalate. Within this range,
processability and absorption rate of resins are
excellent.
The ester plasticizer is for example an ether-free
plasticizer. In this case, there are effects of superior
\ -5
T plasticization efficiency and excellent workability.
Ether-free means that an ether component in the
plasticizer is present at 1,000 ppm or less, 100 ppm. or
less, or 10 ppm or less.
5 The ether component can be for example controlled by
starting material, weight, ratio between reactants,
amount of catalyst added and the like.
The octyl is for example 2-ethylhexyl. In this case, I
10 there are effects of superior processability and ,
I
absorption rate.
The resin composition according to the present
invention comprises the ester plasticizer, and a vinyl
resin or vinyl chloride resin.
Any vinyl resin may be used without particular I
limitation so long as it is accepted in the technical
field. In addition, any vinyl chloride resin may be used
without particular limitation so long as it is accepted in
the technical field.
The ester plasticizer is for example present in an
amount of 5 to 100 parts by weight, based on 100 parts by
weight of the resin.
The resin composition may for example comprise a
filler.
The filler is for example present in an amount of.10
to 300 parts by weight, 50 to 200 parts by weight, or 100
to 200 parts by weight, based on 100 parts by weight of
the resin.
The resin composition for example further compr.i.ses
5 at least one selected from a stabilizing agent, a pigment,
a lubricant and a foaming agent.
The scabilizfng agent, plgment, lubricant and foaming
agent may for example be present in an amount of 0.1 to 20
parts by weight or 1 to 15 parts by weight, based on 100
10 parts by weight of the resin.
Now, preferred examples will be given below for a
better understanding of the present invention. These
examples are provided only to illustrate the present
invention and those skilled in the art will appreciate that
15 various alterations and modifications are possible,
without departing from the scope and spirit of the
invention as disclosed in the accompanying claims.
[Example]
Example 1
1,000 g of dioctyl terephthalate and 70 g of butanol
were added to a reactor equipped with a stirrer, a
condenser and a decanter, and a trans-esterification
reaction was then performed under a nitrogen atmosphere at
25 a reaction temperature of 140"~wi thout any catalyst for 5
/
I
' IrJ hours to obtain a reaction product comprisi~iy 98.9% by
weight of dioctyl terephthalate (hereinafter, DOTP), 1.0%
by weight of butyl octyl terephthalate (hereinafter, BOTP)
and 0.1% by weight of dibutyl terephtha.1.at.e (hereinafter,
' 5 DBTP) .
The reaction product was subjected to combination
dl . , ^ . . - - - -
- - -. - . -. lllatlon to remove the butanol and 2-ethylhexyl
alcohol, thereby preparing a final ester plasticizer.
An ether component was detected in an amount lower
10 than 10 ppm from the prepared ester plasticizer.
Variation in amount of produced'BOTP (%) according to
reaction time during trans-esterification reaction of
Example 1 is shown in FIG. 1.
Example 2
A trans-esterification reaction was performed in the
same manner as in Example 1, except that the reaction
temperature was 160'~ in Example 1, to obtain a reaction
product comprising 76.5% by weight of DOTP, 21.5% by
20 weight of BOTP and 2.0% by weight 'of DBTP. The reaction i
product was distilled in the same manner as in Example 1 I
to prepare a final ester plasticizer.
An ether component was detected in an amount lower
than 10 ppm from the prepared ester plasticizer.
25 Variation in amount of produced BOTP ( % ) according.to
reaction time during trans-esterification reaction of
Example 2 is shown in FIG. 1.
Exeple 3
A trans-esterification reaction was performed in the
same manner as in Example 1, except that an organic acid
catalyst was added in an amount (1.09) corresponding to
0.1% by weight of an amount of added DOTP in Example 1, to
obtain a reaction product comprising 95.0% by weight of
10 DOTP, 4.8% by weight of BOTP and 0.2% by weight of DBTP.
The reaction product was distilled in the same manner as
in Example 1 to prepare a final ester plasticizer.
An ether component was detected in an amount of 300
ppm from the prepared ester plasticizer.
Variation in amount of produced BOTP ( % ) according to
reaction time during trans-esterification reaction of
Example 3 is shown in FIG. 1.
Example 4
A trans-esterification reaction was performed in the
same manner as in Example 2, except that an organic acid
catalyst was added in an amount (1.09) corresponding to
0.1% by weight of an amount of added DOTP in Example 2, to
obtain a reaction product comprising 73.6% by weight of
25 DOTP, 24.0% by weight of BOTP and 2.4% by weight of DBTP.
-4
The reaction product was distilled in the same rnanner as
in Example 2 to prepare a final ester plasticizer.
An ether component was detected in an amount of 500
ppm from the prepared ester plasticizer.
Variation in amount of produced BOTP (%) according to
reaction time during trans-esterification reaction of
Example 4 is shown in FIG. 1.
Example 5
A trans-esterification reaction was performed in the
same manner as in Example 1, except that the reaction
temperature was 180°C and an organic acid catalyst was
added in an amount (1.09) corresponding to 0.1% by weight
of the amount of added DOTP in Example 1, to obtain a
15 reaction product comprising 93.2% by weight of DOTP, 6.3%
by weight of BOTP and 0.5% by weight of DBTP. The reaction
product was distilled in the same manner as in Example 1
to prepare a final ester plasticizer.
Variation in amount of produced BOTP ( % ) according.to
20 reaction time during trans-esterification reaction of
Example 5 is shown in FIG. 1.
Example 6
1,000 g of DOTP and 130 g of BuOH were added to a
25 reactor equipped with a stirrer, a condenser and a
decanter, and a trans-esterification reaction was then
performed using an organic acid catalyst in an amount
(10.0 g) corresponding to 1.0% by weight of the amount of
added DOTP under a nitrogen atmosphere at a reaction
5 temperature of 160"~ for 5 hours to obtain a reaction
product comprising 64.5% by weight of DOTP, 32.0% by
wely11L ul: BOTP d ~ ~3.d5% by w e i y l ~ lu l: DBTP.
The reaction product was subjected to combination
distillation to remove the butanol and the 2-ethylhexyl
10 alcohol, thereby preparing a final ester plasticizer.
A variation in amount of produced BOTP ( % ) according
to reaction time during trans-esterification reaction of
Example 6 is shown in FIG. 2.
A trans-esterification reaction was performed in the
same manner as in Example 6, except that BuOH was used in
an amount of 1009 in Example 6, to obtain a reaction
product comprising 69.9% by weight of DOTP, 27.1% by
20 weight of BOTP and 3.0% by weight of DBTP. The reaction
product was distilled in the same manner as in Example 6
to prepare a final ester plasticizer.
Variation in amount of produced BOTP ( % ) according to
reaction time during trans-esterification reaction of
25 Example 7 is shown in FIG. 2.
Example 8
A trans-esterification reaction was performed in the
same manner as in Example 7, except that butanol and 2-
5 ethylhexyl alcohol were removed by two-step distillation,
instead of the combination distillation, in Example 7, to
-- -- .-- _ _ _ _ - - - - - - --
obeain a final ester plasticizer having a ratio (weight
ratio of DOTP, BOTP and DBTP, of 88.1:10.7:1.2.
10 Example 9
A trans-esterification reaction was performed in the
., same manner as in Example 1, except that, the reaction
temperature was 150°c in Example 1, to obtain a reaction
product comprising 86.5% by weight of DOTP, 12.5% by
15 weight of BOTP and 1.0% by weight of DBTP. The reaction
product was distilled in the same manner as in Example 1
to prepare a final ester plasticizer.
An ether component was detected in. an amount of 200
ppm from the prepared ester plasticizer.
Variation in amount of' produced BOTP ( % ) according to
reaction time during trans-esterification reaction of
Example 9 is shown in FIG. 1.
. .
Example 10
A trans-esterification reaction was performed in the
same manner as in Example 1, except that the reaction
temperature was 170°C in Example 1, to obtain a reaction
product comprising 74.4% by weight of DOTP, 23.1% by
weight of BOTP and 2.5% by weight of DRTP. The reaction
5 product was distilled in the same manner as in Example 1
to prepare a final ester plasticizer.
- - - - -- --
--
variation in-amount of produced BOTP ( % ) according to
reaction time during trans-esterification reaction of i
Example 10 is shown in FIG. 1.
Comparative Example 1
A trans-esterification reaction was performed in the
same manner as in Example 1, except that, in Example 4, I
1,000g of DBTP was used instead of DOTP, 3009 of 2-
15 ethylhexyl alcohol was added instead of BuOH, and the
trans-esterification reaction was performed for 5 hours to
, ~ obtain a reaction product comprising 4.3% by weight 'of
# . DOTP, 1.0% by weight of BOTP and -34.7% by weight of DBTP.
The reaction product was distilled in the same manner as
20 .in Example 1 to prepare a final ester plasticizer.
Comparative Example 2
'A trans-esterification reaction was performed in the
same manner as in Example 4, except that the butanol was
added in an amount (9009) corresponding to 90% by weight
I by weight of DOTP, 72.0% by weight of BOTP and. 10.8% by
weight of DBTP. The reaction product was distilled in the
I same manner as in Examp1.e 1. to prepare a final ester.
5 plasticizer.
_ -_____ - - - - -
Comparative Example 3
498.3 g of terephthalic acid, 111.0 g of n-butanol
I and 976.5 g of 2-ethyl hexanol were subjected to
I 10 esterification reaction using 32 g of 70% methanesulfonic
I acid as an organic acid catalyst in a five-neck round
I flask equipped with a temperature sensor, a mechanical
I stirrer, a condenser, a decanter and a nitrogen injector,
I for about 5 hours, while slowly elevating temperature from
I 15 140"~ to 180°c, and the reaction product was cooled and
washed with water once and dealcoholized by I heating under .*
I I reduced pressure to prepare a final ester plasticizer.
The prepared ester plasticizer comprised 19.5% by
1 weight of DOTP, 75.5% by weight of BOTP and 5.0% by weight
I
i 20 . of DBTP, and the ether component. was present at 32,000
[Test Example]
Physical properties of plasticizers prepared in
25 Examples 1 to 10 and Comparative Examples 1 and 2 were ' I
measured in accordance with the followiriy method and
results thus obtained are shown in the following Table 1
and FIGS. 1 and 2.
* Contents (wt%) of DOTP, BOTP and DRTP: mes.si.lred
5 . using a gas chromatograph produced by Agilent Technologies
(Agilent 7890 GC, column: HP-5, carrier gas: helium) .
* Ether content: measured using a gas chromatograph
produced by Agilent Technologies (Agilent 7890 GC, column:
HP-5, carrier gas: helium) .
* Absorption rate: evaluated by measuring a time at
which a resin is mixed with a plasticizer using a mixer
(product name : Brabender) under mixing conditions of 77 "C,
60 rpm, PVC (product name: LS 100) 400 g and plasticizer
200 g, and a torque of the mixer is then stabilized.
* Foamability: 100 parts by weight of PVC (product
name: PB 900), 75 parts by weight of a plasticizer, 130
parts by weight of a filler, 4 parts by weight of a
stabilizing agent, 13 parts by weight of Ti02 and 3 parts
by weight of a foaming agent were mixed to obtain a sol,
20 the sol was thinly coated on a base paper (paper) used for
wallpaper and was then foamed at 230"~f or 70 seconds, the
cross-section of the paper was cut, a cell state was
measured using an optical microscope, and size, shape and
arrangement uniformity of the cell were evaluated on a
25 scale of 1 (good) to 5 (bad).
TABLE 1
*Foamability: 1 (Good) to 5 (Bad)
In accordance with the method for preparing ester
plasticizers according to the present invention, butyl
octyl terephthalate having a desired composition can be
freely prepared, and the ester plasticizers prepared
therefrom (Examples 1 to 10) have high absorption rates of
3:42 to 6:10 (m:s) and exhibit superior workability and
foamability of resins, as can be seen from Table 1 above.
However, it can be seen that ester plasticizers
(Comparative Examples 1 and 2) prepared by a method which
is different from the method for preparing an ester
plasticizer of the present invention aggravates gelation
due to considerably high absorption rate and have
' considerably low workability and foamability.
In addition, it can be seen that the method for
Ex. 9
Ex. 10
Comp. Ex. 1
Comp. Ex. 2
Comp. EX. 3
Not added
Not added
0.1
0.1
4.5
150
170
160
160
140-180
5
5
5
5
5
550
4:25
2:13
252
250
3
1
4
3
3
-+i / preparing an ester plasticizer according to the present
invention has a short reaction time and consumes butyl
'alcohol well soluble in water, and does not yield byproducts,
thus advantaqeously causing almost no wast.ewater,
5 disposal problems.
As can be seen from FIG. 1, in the case of Examples 1
- t-..t .- .3 -aKd Examples 9 and -1 0, the trans-esterification
reaction according t'o the present inventidn, regardless of
using of a catalyst, causes a great increase in amount of
10 pr.oduced BOTP at a reaction temperature which is higher
than about 140°C and is lower than about 180°C and enables
easy production of an ester plasticizer having a desired
compositional ratio.
In addition, as can be seen from FIG. 2 (Examples 6
15 and 7), the trans-esterification reaction according to the
present invention causes a constant increase in amount -of
produced BOTP as an amount of butyl' alcohol added
increases.
In addition, it 'can be seen that, when residual
20 alcohol is removed by other distillation method after the
trans-esterification reaction according to the present
invention, two-step distillation (Example 8) exhibits a
great decrease in amount of produced BOTP, as compared to
combination distillation (~xam~1e6. sa nd 7').
In addition, it can be seen that, when an ester
plasticizer is prepared by esterification reaction
(Comparative Example 3 ) , as compared to the transesterification
reaction according to the present
invention, it is relatively d.i ffi.cidll.t to control a
5 preparation process, there are many problems associated
with wastewater disposal, and it is not easy to obtain a
desired ester plasticizer composition.

We Claim:
1. A method for preparing an ester plasticizer comprising trans-esterifying 100 parts
by weight of dioctyl terephthalate with 0.1 to 89.9 parts by weight of butyl
alcohol.
2. The method according to claim 1, wherein the trans-esterification reaction
converts the dioctyl terephthalate into 30 to 99% by weight of the dioctyl
terephthalate, 1 to 70% by weight of butyl octyl terephthalate, and 0 to 20% by
weight of dibutyl terephthalate.
3. The method according to claim 1, wherein the butyl alcohol is present in an
amount of 1 to 50 parts by weight.
4. The method according to claim 1, wherein a molar ratio of the dioctyl
terephthalate to the butyl alcohol is 1:0.005 to 1:5.0.
5. The method according to claim 4, wherein the molar ratio of the dioctyl
terephthalate to the butyl alcohol is 1:0.2 to 1:2.5.
6. The method according to claim 1, wherein the trans-esterification reaction is
performed at 120°C to 190°C.
7. The method according to claim 1, wherein the trans-esterification reaction is a
non-catalytic reaction.
8. A method for preparing an ester plasticizer comprising:
a) trans-esterifying 100 parts by weight of dioctyl terephthalate with 0.1 to
89.9 parts by weight of butyl alcohol; and
13
b) removing unreacted butyl alcohol and octyl alcohol as a reaction byproduct
by combination distillation.
9. An ester plasticizer comprising:
30 to 99% by weight of dioctyl terephthalate;
1 to 70% by weight of butyl octyl terephthalate; and
0 to 20% by weight of dibutyl terephthalate.
10. The ester plasticizer according to claim 9, wherein the ester plasticizer is an etherfree
plasticizer.
11. The ester plasticizer according to claim 9, wherein the octyl is 2-ethylhexyl.
12. A resin composition comprising:
the ester plasticizer according to any one of claims 9 to 11; and
a vinyl resin or a vinyl chloride resin.