[TECHNICAL FIELD]
Cross-reference to Related Applications
[0001] The present application claims the benefit of priority
based on Korean Patent Application No. 10-2020-0100049, filed
10 on August 10, 2020, the entire contents of which are
incorporated herein by reference.
Technical Field
[0002] The present invention relates to a citrate-based
15 plasticizer composition including a hybrid citrate of lower
and higher alkyl radicals of the components in the composition,
and a resin composition comprising the same.
[BACKGROUND ART]
20 [0003] Generally, plasticizers are obtained through the
reaction of alcohols with polycarboxylic acids such as phthalic
acid and adipic acid to form corresponding esters. In addition,
considering the internal and external regulations on harmful
phthalate-based plasticizers to the human body, studies are
25 being continued on plasticizer compositions which may replace
2
phthalate-based plasticizers such as terephthalate-based,
adipate-based and other polymer-based plasticizers.
[0004] Meanwhile, regardless of the type of industry
including plastisol type of industry of flooring materials,
5 wallpaper, soft and hard sheets, etc., calendaring type of
industry, extrusion/injection compound type of industry, and
the demand for eco-friendly products is increasing. In order
to reinforce the quality properties, processability and
productivity of the finished products, a suitable plasticizer
10 is required considering discoloration, migration, mechanical
properties, etc.
[0005] According to the properties required by the types of
industry in various areas of usage, such as tensile strength,
elongation rate, light resistance, migration, gelling
15 properties and absorption rate, supplementary materials such
as a plasticizer, a filler, a stabilizer, a viscosity
decreasing agent, a dispersant, a defoaming agent and a foaming
agent are mixed with a PVC resin.
[0006] For example, in the case of applying di(2-ethylhexyl)
20 terephthalate (DEHTP) which is relatively cheap and widely
used among plasticizer compositions which may be applied to
PVC, hardness or sol viscosity was high, absorption rate of a
plasticizer was relatively slow, and migration and stress
migration were not good.
25 [0007] As improvements on the above limitations, the
3
application of a transesterification product with butanol as
a plasticizer, in a composition including DEHTP may be
considered. In this case, plasticization efficiency is
improved, but volatile loss or thermal stability is inferior
5 and mechanical properties are somewhat degraded, and the
improvement of physical properties is required. Accordingly,
generally, there is no solution but employing a method
compensating the defects through mixing with a second
plasticizer at the present time.
10 [0008] However, in the case of applying the second plasticizer,
there are drawbacks of generating unexpected defects as follows:
the change of the physical properties is hard to predict; the
application may become a factor of increasing the unit cost of
the product; the improvement of the physical properties is not
15 clearly shown except for specific cases; and problems relating
to compatibility with a resin may arise.
[0009] In addition, if a material like tri(2-ethylhexyl)
trimellitate or triisononyl trimellitate is applied as a
trimellitate-based product in order to improve the inferior
20 migration and loss properties of the DEHTP products, migration
or loss properties may be improved, but plasticization
efficiency may be degraded, and a great deal of the material
is required to be injected to provide a resin with suitable
plasticization effect, and considering the relatively high
25 unit price of the products, commercialization thereof is
4
impossible.
[0010] Accordingly, the development of products for solving
the environmental issues of the conventional phthalate-based
products or products for improving inferior physical
5 properties of the eco-friendly products for improving the
environmental issues of the phthalate-based products is
required.
[DISCLOSURE OF THE INVENTION]
10 [TECHNICAL PROBLEM]
[0011] The present invention provides a plasticizer
composition which includes a citrate in which lower and higher
alkyl radicals are suitably controlled and combined, thereby
maintaining and improving mechanical properties and stress
15 resistance to equal or better levels than the conventional
plasticizer and at the same time, markedly improving light
resistance and heat resistance, while having suitable balance
between migration and loss properties and plasticizer
efficiency.
20
[TECHNICAL SOLUTION]
[0012] To solve the tasks, according to an embodiment of the
present invention, there is provided a plasticizer composition
comprising a citrate-based composition comprising three or
25 more citrates of the following Formula 1, wherein an alkyl
5
group of the citrate is derived from a C4 alcohol and a C6
alcohol, the C4 alcohol comprises one or more selected from
the group consisting of n-butanol and isobutanol, and the C6
alcohol comprises one or more selected from the group
5 consisting of 1-hexanol, 1-methylpentanol, 2-methylpentanol,
3-methylpentanol, 4-methylpentanol, 1,1-dimethylbutanol, 1,2-
dimethylbutanol, 1,3-dimethylbutanol, 2,2-dimethylbutanol,
2,3-dimethylbutanol, 3,3-dimethylbutanol, 1-ethylbutanol, 2-
ethylbutanol, 3-ethylbutanol and cyclopentyl methanol:
10 [0013] [Formula 1]
[0014] in Formula 1, R1 to R3 are each independently an alkyl
group of 4 or 6 carbon atoms, and R4 is hydrogen.
[0015] In order to solve the tasks, according to another
15 embodiment of the present invention, there is provided a resin
composition comprising 100 parts by weight of a resin, and 5
to 150 parts by weight of the plasticizer composition.
[0016] The resin may be one or more selected from the group
consisting of a straight vinyl chloride polymer, a paste vinyl
20 chloride polymer, an ethylene vinyl acetate copolymer, an
ethylene polymer, a propylene polymer, polyketone, polystyrene,
polyurethane, polylactic acid, natural rubber and synthetic
rubber.
6
[ADVANTAGEOUS EFFECTS]
[0017] The plasticizer composition according to an embodiment
of the present invention, if used in a resin composition, may
5 maintain and improve mechanical properties and stress
resistance to equal or better levels when compared to the
conventional plasticizer, and at the same time, markedly
improve physical properties such as migration and light
resistance, while having suitable balance between loss
10 properties and plasticization efficiency.
[MODE FOR CARRYING OUT THE INVENTION]
[0018] It will be understood that terms or words used in the
present disclosure and claims should not be interpreted as
15 having a meaning that is defined in common or in dictionaries,
however should be interpreted in consistent with the technical
scope of the present invention based on the principle that
inventors may appropriately define the concept of the terms to
explain the invention at his best method.
20
[0019] Definition of terms
[0020] The term “composition” as used in the present
disclosure includes a mixture of materials including the
corresponding composition as well as a reaction product and a
25 decomposition product formed from the materials of the
7
corresponding composition.
[0021] The term “straight vinyl chloride polymer” as used in
the present disclosure may be one type of vinyl chloride
polymers and polymerized by suspension polymerization, bulk
5 polymerization, etc., and may refer to a polymer having a
porous particle shape in which a large number of pores having
a size of tens to hundreds of micrometers, no cohesiveness,
and excellent flowability are dispersed.
[0022] The term “paste vinyl chloride polymer” as used in the
10 present disclosure may be one type of vinyl chloride polymers
and polymerized by microsuspension polymerization, microseed
polymerization, emulsion polymerization, etc., and may refer
to a polymer having minute particles without pores and a size
of tens to thousands of nanometers, cohesiveness, and inferior
15 flowability.
[0023] The terms "comprising", and “having” and the
derivatives thereof in the present invention, though these
terms are particularly disclosed or not, do not intended to
preclude the presence of optional additional components, steps,
20 or processes. In order to avoid any uncertainty, all
compositions claimed by using the term “comprising” may include
optional additional additives, auxiliaries, or compounds,
including a polymer or any other materials, unless otherwise
described to the contrary. In contrast, the term “consisting
25 essentially of ~” excludes unnecessary ones for operation and
8
precludes optional other components, steps or processes from
the scope of optional continuous description. The term
“consisting of ~” precludes optional components, steps or
processes, which are not particularly described or illustrated.
5
[0024] Measurement methods
[0025] In the present disclosure, the content analysis of the
components in a composition is conducted by gas chromatography
measurement using a gas chromatography equipment of Agilent
10 Co. (product name: Agilent 7890 GC, column: HP-5, carrier gas:
helium (flow rate of 2.4 ml/min), detector: F.I.D., injection
volume: 1 μl, initial value: 70°C/4.2 min, end value: 280°C/7.8
min, program rate: 15°C/min).
[0026] In the present disclosure, “hardness” means Shore
15 hardness (Shore “A” and/or Shore “D”) at 25°C and is measured
in conditions of 3T 10s using ASTM D2240. The hardness may be
an index for evaluating plasticization efficiency, and the
lower the value is, the better the plasticization efficiency
is.
20 [0027] In the present disclosure, “tensile strength” is
obtained according to an ASTM D638 method by drawing a specimen
in a cross head speed of 200 mm/min (1T) using a test apparatus
of U.T.M (manufacturer: Instron, model name: 4466), measuring
a point where the specimen is cut, and calculating according
25 to the following Mathematical Formula 1:
9
[0028] [Mathematical Formula 1]
Tensile strength (kgf/cm2) = load value (kgf)/thickness
(cm) x width (cm)
[0029] In the present disclosure, “elongation rate” is
5 obtained according to an ASTM D638 method by drawing a specimen
in a cross head speed of 200 mm/min (1T) using the U.T.M,
measuring a point where the specimen is cut, and calculating
according to the following Mathematical Formula 2:
[0030] [Mathematical Formula 2]
10 Elongation rate (%) = length after elongation/initial
length x 100
[0031] In the present disclosure, “migration loss” is
obtained according to KSM-3156, by which a specimen with a
thickness of 2 mm or more is obtained, glass plates are
15 attached onto both sides of the specimen, and a load of 1
kgf/cm2 is applied. The specimen is stood in a hot air
circulation type oven (80°C) for 72 hours, then taken out
therefrom and cooled at room temperature for 4 hours. Then,
the glass plates attached onto both sides of the specimen are
20 removed, the weights before and after standing a glass plate
and a specimen plate in the oven are measured, and the
migration loss is calculated according to Mathematical Formula
3 below.
[0032] [Mathematical Formula 3]
25 Migration loss (%) = {[(weight of initial specimen) –
10
(weight of specimen after standing in oven)]/(weight of initial
specimen)} x 100
[0033] In the present disclosure, “volatile loss” is obtained
by processing a specimen at 80°C for 72 hours and then,
5 measuring the weight of the specimen.
[0034] [Mathematical Formula 4]
Volatile loss (wt%) = {[(weight of initial specimen) –
(weight of specimen after processing)]/(weight of initial
specimen)} x 100
10 [0035] In the case of the various measurement conditions, the
details of the conditions of the temperature, the speed of
revolution, the time, etc., may be somewhat changed according
to situations, and if the conditions are different, a
measurement method and its conditions are required to be
15 separately indicated.

CLAIMS
1. A plasticizer composition comprising a citrate-based
composition comprising three or more citrates of the following
5 Formula 1, wherein
an alkyl group of the citrate is derived from a C4 alcohol
and a C6 alcohol,
the C4 alcohol comprises one or more selected from the
group consisting of n-butanol and isobutanol, and
10 the C6 alcohol comprises one or more selected from the
group consisting of 1-hexanol, 1-methylpentanol, 2-
methylpentanol, 3-methylpentanol, 4-methylpentanol, 1,1-
dimethylbutanol, 1,2-dimethylbutanol, 1,3-dimethylbutanol,
2,2-dimethylbutanol, 2,3-dimethylbutanol, 3,3-dimethylbutanol,
15 1-ethylbutanol, 2-ethylbutanol, 3-ethylbutanol and cyclopentyl
methanol:
[Formula 1]
in Formula 1,
20 R1 to R3 are each independently an alkyl group of 4 or 6
carbon atoms, and R4 is hydrogen.
2. The plasticizer composition according to claim 1, wherein
44
the citrate-based composition comprises:
a lower alkyl-based citrate comprising a lower nonhybrid
citrate having an alkyl group derived from three C4 alcohols,
and a lower hybrid citrate having an alkyl group derived from
5 two C4 alcohols and an alkyl group derived from one C6 alcohol;
and
a higher alkyl-based citrate comprising a higher hybrid
citrate having an alkyl group derived from two C6 alcohols and
an alkyl group derived from one C4 alcohol, and a higher
10 nonhybrid citrate having an alkyl group derived from three C6
alcohols.
3. The plasticizer composition according to claim 1, wherein
a weight ratio of the C4 alcohol and the C6 alcohol is 5:95 to
15 95:5.
4. The plasticizer composition according to claim 1, wherein
the C6 alcohol comprises 1-hexanol, 2-methylpentanol and 3-
methylpentanol.
20
5. The plasticizer composition according to claim 4, wherein
the C6 alcohol further comprises cyclopentyl methanol.
6. The plasticizer composition according to claim 1, wherein
25 the C6 alcohol comprises 1-hexanol, and one or more selected
45
from the group consisting of 2-methylpentanol, 3-
methylpentanol and cyclopentyl methanol, and
the 1-hexanol is comprised in 60 wt% or less based on a
total weight of the C6 alcohol.
5
7. The plasticizer composition according to claim 2, wherein
a weight ratio of the lower alkyl-based citrate and the higher
alkyl-based citrate is 1:99 to 99:1.
10 8. The plasticizer composition according to claim 7, wherein
the weight ratio of the lower alkyl-based citrate and the
higher alkyl-based citrate is 2:98 to 95:5.
9. The plasticizer composition according to claim 2, wherein
15 a weight ratio of the lower nonhybrid citrate and the lower
hybrid citrate in the lower alkyl-based citrate is 2:98 to
90:10.
10. The plasticizer composition according to claim 2, wherein
20 a weight ratio of the higher nonhybrid citrate and the higher
hybrid citrate in the higher alkyl-based citrate is 5:95 to
95:5.
11. A resin composition, comprising:
25 100 parts by weight of a resin; and 5 to 150 parts by
46
weight of the plasticizer composition of claim 1.
12. The resin composition according to claim 11, wherein the
resin is one or more selected from the group consisting of a
5 straight vinyl chloride polymer, a paste vinyl chloride polymer,
an ethylene vinyl acetate copolymer, an ethylene polymer, a
propylene polymer, polyketone, polystyrene, polyurethane,
polylactic acid, natural rubber and synthetic rubber.
10