Hello acp,
Following are patented processes for synthesis of Zinc Acrylate. The
second provides for a modified Zinc Acrylate fine powder. These
information are the portions of respective U.S. patent numbers 5789616
and 6278010 that describe these processes. Full patent information can
be found by looking up these numbers at the U.S. Patent and Trademark
Office web site: www.uspto.gov.
Please let me know how well this answer meets your requirements.
vitalmed
1) U.S. PATENT: US 5789616
Method for production of zinc acrylate
Inventor:
Kobayashi, Keiji, Chiba, JP
Kodama, Yukihisa, Chiba, JP
Saotome, Minoru, Kanagawa, JP
Saito, Yoshinori, Chiba, JP
Assignee:
Bridgestone Sports Co., Ltd, (03), JP
Nippon Shokubai Co., Ltd, (03), JP
Nihon Joyu Kogyo Co., Ltd., (03), JP
Abstract: A method is provided for the production of zinc acrylate
which possesses an essentially fine constitution, permits easy
pulverization into a fine powder, and, when kneaded with a rubber
composition, attains uniform diffusion in a state very rarely inducing
fast adhesion or formation of cluster. The fine zinc acrylate powder
is obtained by a method which comprises causing acrylic acid and a
higher fatty acid of 12-30 carbon atoms to react with zinc oxide in an
organic solvent while continuing dispersion of the zinc oxide in the
organic solvent in the presence of an anionic surfactant…
Now, this invention will be described more specifically below.
The zinc oxide to be appropriately used in this invention may be a
standard solid compound in a powdery state. Though it is preferred to
be in a highly purified form, it may contain zinc hydroxide. As
respects the amount of zinc oxide to be used, though the zinc oxide is
generally used in the reaction in an equivalent weight
stoichiometrically to the total weight of acrylic acid and a higher
fatty acid, it suffices to adjust the amounts of acrylic acid and the
higher fatty acid to be used so that the product may have a zinc
acrylate content in the range of 80-98% by weight, preferably 85-95%
by weight. When the zinc acrylate is used as a weight controller as
when it is used for the core of a solid golf ball, for example, it may
be safely used in an excess state so long as the excess amount causes
a hindrance.
When the acrylic acid happens to be used in an excess amount, the
excess acrylic acid may be expelled by distillation and then dried in
conjunction with the organic solvent and the water formed by the
reaction during the separation and recovery of the zinc acrylate as
the reaction product.
The acrylic acid to be used in this invention is preferred to be in a
form not diluted with water, though it tolerates inclusion of an
insignificant amount of water. It can safely contain therein such a
substance as, for example, hydroquinone or hydroquinone monomethyl
ether which is generally used as a polymerization inhibitor. The
amount of the acrylic acid to be used is in the range of 100-250 parts
by weight, preferably 150-200 parts by weight, based on 100 parts by
weight of the zinc oxide.
The higher fatty acid to be used in this invention is a fatty acid
having 12-30 carbon atoms. As typical examples of the higher fatty
acid, lauric acid, myristic acid, palmitic acid, stearic acid, behenic
acid, oleic acid, and linoleic acid may be cited. These higher fatty
acids may be used selectively in the form of a mixture. Among the
higher fatty acids mentioned above, palmitic acid and stearic acid
prove particularly favorable. The higher fatty acid may be used in its
unmodified form or as dissolved in advance in the organic solvent or
acrylic acid destined to be used in the reaction. The dissolution,
when necessary, may be attained by application of heat.
The amount of the higher fatty acid mentioned above to be added is
2-50 parts by weight, preferably 10-35 parts by weight, based on 100
parts by weight of the zinc oxide. If the amount thus added is less
than 2 parts by weight, the objects of this invention will not be
fully accomplished because the zinc acrylate during or after the
production is not easily fixed or diffused. If the amount exceeds 50
parts by weight, the excess higher fatty acid will produce an adverse
effect of impairing the properties of the zinc acrylate. The optimum
amount of addition is decided within the range of the purpose for
which the zinc acrylate is used.
As typical examples of the anionic surfactant to be used in this
invention, succinic dialkyl esters of sodium sulfonate such as
alkylbenzene sodium sulfonate, secondary alcohol succinic half ester
salts, alkyl sulfosuccinates, sodium diamyl sulfosuccinate, sodium
dihexyl sulfosuccinate, sodium dioctyl sulfosuccinate, and monoethyl
monododecyl sodium succinate, alkyl sulfates such as lauryl sulfate,
tetradecyl sulfate, and oleyl sulfate, sulfuric sodium esters such as
amide sulfonate and ricinoleic esters, [alpha]-sulfofatty alkyl ester
salts, monosodium [alpha]-phosphorofatty esters, and sodium dialkyl
phosphates. These anionic surfactants may be used selectively in the
form of a mixture. Among other anionic surfactants enumerated above,
sodium dioctyl sulfosuccinate proves particularly advantageous because
it is capable of preventing the zinc acrylate during or after the
production thereof from adhering to surfaces, forming clusters, and
emitting dust. The amount of the anionic surfactant to be used is
0.03-1.5 parts by weight, preferably 0.1-1 part by weight, based on
100 parts by weight of zinc oxide. The anionic surfactant is generally
used as mixed in advance with the organic solvent destined to be used
in the reaction.
The organic solvent to be used in this invention is properly a
hydrocarbon compound. As typical examples of the hydrocarbon compound,
methanol, ethanol, isopropanol, benzene, toluene, xylene, n-hexane,
and cyclohexane may be cited. Preferably, it is insoluble in water and
is capable of forming an azeotropic mixture with water.
Now, a concrete preferred embodiment of this invention will be
described below.
In a reaction vessel provided with a stirrer of a fully satisfactory
stirring capacity and a thermal condenser, the organic solvent and the
anionic surfactant are placed in prescribed amounts and kept stirred
and the zinc oxide is added thereto and they are heated together to
10[degree(s)]-70[degree(s)] C., preferably 30[degree(s)]-50[degree(s)]
C. The resultant suspension is kept at the temperature and the higher
fatty acid is added thereto to form the zinc salt of the higher fatty
acid. The time for the addition and the time for the reaction may be
suitably selected in the range of 0.5-10 hours, preferably 1-5 hours,
depending on the reaction temperature. Then, the reaction mixture is
kept, when necessary by cooling, at 10[degree(s)]-70[degree(s)] C.,
preferably 15[degree(s)]-50[degree(s)] C., and the acrylic acid is
added thereto to form zinc acrylate. The time for the addition and the
time for the reaction may be suitably selected in the range of 0.5-10
hours, preferably 2-7 hours, depending on the reaction temperature. If
the reaction temperature is lower than 10[degree(s)] C., the reaction
velocity will be unduly low and the reaction will consume an unduly
long time. Conversely, if the reaction temperature exceeds
70[degree(s)] C., the acrylic acid and the zinc acrylate will induce a
polymerization reaction and the product will suffer degradation of
quality.
The separation of the zinc acrylate for recovery after the reaction
may be attained by separating the water formed by the reaction and the
organic solvent through filtration from the interior of the reaction
vessel and drying the zinc acrylate which remains after the filtration
at a temperature of 10[degree(s)]-70[degree(s)] C. When the reaction
vessel happens to be a kneader blender which is provided with a
stirrer possessing scraping blades, the procedure of stirring the
reaction mixture in its unmodified form and meanwhile distilling the
reaction mixture at a temperature of 10[degree(s)]-70[degree(s)] C.,
preferably 15[degree(s)]-50[degree(s)] C., optionally under a reduced
pressure to expel the excess acrylic acid, the organic solvent, and
the water formed by the reaction and drying the residue of
distillation proves a preferred embodiment permitting simplification
of facilities and allowing efficiency of operation. The time for the
distillation and the time for the drying may be suitably selected in
the range of 1-20 hours, depending on the temperature. If the
temperature of distillation and drying is lower than 10[degree(s)] C.,
the reaction will consume an unduly long time. Conversely, if the
reaction temperature exceeds 70[degree(s)] C., the acrylic acid and
the zinc acrylate will induce a polymerization reaction and the
product will suffer degradation of quality. In this case, the
expulsion of the water formed by the reaction and the organic solvent
is preferred to resort to azeotropic distillation with water.
2) U.S. PATENT: US 6278010
Process for producing modified zinc acrylate fine powder
Inventor:
Tsou, Chiu-Peng, Ping-Chen, TW
Chen, Ruey-Tsan, Ping-Chen, TW
Su, Chang-Min, Ping-Chen, TW
Assignee:
Kuo Ching Chemical Co., Ltd., (03), Taoyuan County, TW
Abstract: An improved process for producing modified zinc acrylate
fine powder is disclosed, comprising adding acrylic acid in a organic
liquid medium and reacting in the presence of zinc oxide and fatty
acid, and after completing of the reaction, adding nonionic
surfactant, blending homogeneously, removing said organic medium and
water by distillation under reduced pressure and simple pulverizing.
The process can attains uniform diffusion in a state very rarely
inducing fast adhesion or formation of cluster in the drying step,
and, permits easy pulverization into a fine powder, 99% of which has a
particle size<44 [mu]m and thereby can be used directly without
needing any sieving.
As stated above, the invention provides an improved process for
producing zinc acrylate fine powder, comprising the steps of:
1. Stirring under heating zinc oxide and fatty acid in a liquid
medium, adding acrylic acid at controlled temperature, and continuing
heating till a constant pH of the solution;
2. Adding 0.02 to 1.0% by weight of a nonionic surfactant in the
reaction mixture containing zinc acrylate in step 1 and stirring to
form a homogeneous cream; and
3. Removing organic liquid medium and water by distillation under
reduced pressure, and pulverizing to afford directly a zinc acrylate
fine powder.
In the process for producing zinc acrylate fine powder according to
the invention, the ratio among amounts of zinc oxide, fatty acid,
acrylic acid and the organic liquid medium used may have an effect on
the particle size, the zinc content and the content of acryl group of
the modified zinc acrylate powder thus produced. Therefore, the mole
ratio of zinc oxide, fatty acid and acrylic acid used in the process
of the invention is suitably controlled in the range of
0.50-0.55/0.02-0.04/1.00, while the amount of the organic liquid
medium should be more than 0.8 times, preferably 1 to 4 times of the
total amount of reactants.
Zinc oxide used in the process according to the invention is
preferably a powder. Fatty acid used in the process of the invention
is selected from palmitic acid and stearic acid. The liquid medium
that can be used in the invention is selected from C6 to C10 aromatic
hydrocarbon, and may be benzene, toluene, or xylene. The liquid medium
may contain 0.5 to 10% of water.
The temperature in the course of adding material and reaction may be
in the range of 40 to 75[degree(s)] C., preferably in the range of 45
to 65[degree(s)] C.
The nonionic surfactant useful in the invention is selected from one
or more polyoxyethylene alkyl ether. Among the commercial available
polyoxyethylene alkyl ethers, those having a hydrophilic-lipophilic
balance (HLB) value in the range of 8 to 17 can give better effect,
and examples thereof are those sold under trade names as Sinopol 1830
(HLB 16.6), Sinopol 1807 (HLB 10.7), Sinopol 1536 (HLB 12.8), Sinopol
1307 (HLB 12.7), Sinopol 1100H (HLB 12.7).
The modified zinc acrylate fine powder produced by the process
according to the invention is a zinc acrylate mixture comprising zinc
acrylate powder coated with a fatty acid or salt thereof, and is
characterized in that it has a content of zinc acrylate of 90[+-]5 wt
%, an as content of 35 to 40 wt %, and an acryl content of 50 to 58 wt
%. The characteristics of particle size of the modified zinc acrylate
fine powder produced according to the process of the invention
exhibits as, by way of an example, that analyzed for the powder
obtained in Example 1: 99+% of particles<44 [mu]m, 26.15% of
particles<10 [mu]m and 9.55% of particles<5 [mu]m, such that the
as-produced powder need not sieving and can meet the requirement of
the market in terms of the fineness and uniformity.
The technical feature of the process according to the invention
comprises taking advantage of the characteristics of the zinc salt of
fatty acid as a good dispersant for a powder, thereby, renders
stirring of the reaction mixture in the course of adding acrylic acid
more easy and thus a uniform reaction. In comparison with prior art
technique, this can reduce considerably time for the addition of
reactants and for completion of reaction, and further, the zinc
acrylate powder thus produces is more uniform. In other words,
according to the invention, the selection of the nonionic surfactant
having the above-specified HLB value and addition of it into the zinc
acrylate reaction product can facilitate uniform dispersion of the
powder, water and the organic liquid medium, improve the efficiency
for removing organic liquid medium and water through distillation
under reduced pressure in the course of drying, as well as can avoid
the powder from sticking on the stirring blade and the wall of the
reactor during operation. Since zinc acrylate fine powder produced
according to the invention has 99% of its particles a particle size
of<44 [mu]m, it is superior than those produced by any prior art
technique in that it can be used without needing any sieving. |
