JPH06220136A - Allyl ether compound copolymer and blood-separating agent containing same - Google Patents

Abstract

PURPOSE:To provide the subject copolymer having a prescribed number-average mol.wt., excellent in separation operability, and useful as a blood-separating agent, etc., without causing a physical or chemical change by copolymerizing a specific allyl monomer, a specific alpha-olefin, a specific monomer, etc., in a specified ratio. CONSTITUTION:(A) 20-98mol.% of a monomer of the formula (R is lower alkyl; n is 0, 1), (B) 2-50mol.% of a 6-20C alpha-olefin and/or an alkylvinyl ether wherein the alkyl group has 2-20 carbon atoms, and (C) 0-30mol.% of a monomer having a copolymerizable ethylenically unsaturated double bond except the components A and B, such as styrene, in the presence of a radical polymerization initiator such as di-t-butyl peroxide to provide the objective copolymer having a number- average mol.wt. of 500-10000. The blood-separating agent contains the copolymer as a main component.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an allyl ether compound type copolymer and a blood separating agent using the same. More specifically, when a novel copolymer of an allyl ether compound and a serum component and a blood clot component coexisting in blood or a plasma component and a blood cell component are separated by utilizing the difference in specific gravity between them, The present invention relates to a blood separating agent which can be used for the purpose of forming a partition wall between both components by imparting a specific gravity thereof and facilitating the separation operation of these both components.

[0002]

2. Description of the Related Art Conventionally, various compounds have been known as a separating agent used in such a separating operation. For example, silicone oil (JP-A-54-2120 etc.), acrylic polymer oil (JP-A-54-63797 etc.), chlorinated polybutene oil (JP-A-57-9718 etc.), α-
Olefin / maleic acid diester copolymer
2-199644, etc.) or a cyclopentadiene oligomer (JP-A-1-295163, etc.) as a main component, and silica or clay as a thixotropic agent for adjusting specific gravity or viscosity or maintaining shape It is known that inorganic fine particles are added.

On the other hand, recently, drug therapy has been actively carried out in clinical practice, and there is a growing need to measure the blood concentration of the drug accurately and rapidly. Is being used more and more frequently because it allows simple and quick blood separation.

[0004]

However, since these blood-based blood-separating agents are not sufficiently compatible with thixotropic agents, they are not suitable for heat treatment, long-term storage or centrifugation. Phase separation occurs underneath, deterioration of the partition function due to changes in the physical properties of the gel and contamination of separated components due to oil separation are easy to occur.In addition, heat resistance is insufficient, so decomposition in the adjustment, filling, and sterilization processes There is a problem in that substances are likely to be generated and that the separated components are liable to be contaminated. Further, when a compatible oil is mixed in order to adjust the specific gravity and the viscosity, due to the difference in affinity with the thixotropic agent, a change in the properties of the blood separating agent over time occurs, and the thermal stability is improved. It has a drawback that it is bad, and when oil having a low specific gravity is mixed, the separated components are liable to be contaminated. Further, when the separating agent contains a volatile component having a low molecular weight, the inner wall of the vacuum blood collection tube becomes water repellent, which causes a problem such as slow blood coagulation.

Further, when a conventional blood separating agent is used,
For example, hospital pharmacy vol. 12, No. 6, 401 (19
86), Kyushu Pharmaceutical Bulletin No. 40, 39 (1986), etc., the problem that the drug component contained in serum decreases with time due to the influence of the blood separating agent used. There is. This is because the drug component to be measured is absorbed by the blood separating agent due to the influence of the blood separating agent used during the blood separating operation, and the blood concentration thereof decreases over time. The cyclopentadiene oligomer described above is excellent in terms of drug adsorption, but has a drawback that it contains a large amount of volatile components for use in a vacuum blood collection tube.

Therefore, it is not appropriate to use a conventional blood separating agent for the purpose of measuring the blood concentration of a certain drug, and there has been a strong demand for the development of a blood separating agent that improves these points.

[0007]

An object of the present invention is to provide a polymer suitable for obtaining a practically excellent blood separating agent which does not have these drawbacks, and a blood separating agent using the same. . The present inventors have conducted extensive studies in order to achieve such an object, and as a result, a specific allyl ether compound and α-
The present invention has been accomplished by finding that a copolymer containing an olefin and / or an alkyl vinyl ether as an essential component is a practically excellent blood separating agent. That is, the gist of the present invention is the following general formula (I)

[0008]

[Chemical 2]

(In the formula, R represents a lower alkyl group, and n represents 0 or 1.) 20-98 mol% of a unit derived from the monomer (a) represented by α- having 6 to 20 carbon atoms.
Carbon number of olefin and / or alkyl group is 2 to 2
2 to 50 mol% of a unit derived from an alkyl vinyl ether (b) of 0, and a monomer (c) having a copolymerizable ethylenically unsaturated bond other than the above (a) and (b)
The allyl ether compound-based copolymer having a number average molecular weight of 500 to 10,000 containing 0 to 30 mol% of the unit derived from and a blood separating agent containing the copolymer as a main component.

The present invention will be described in detail below. The monomer (a) in the present invention is represented by the above general formula (I). Examples of the lower alkyl group represented by R include a lower alkyl group having 1 to 4 carbon atoms such as methyl, ethyl and propyl, and n represents 0 or 1. R is preferably a lower alkyl group having 1 to 2 carbon atoms. The monomer (a) represented by the general formula (I) has the following general formula:

[0011]

[Chemical 3]

(In the formula, R and n have the same meanings as described above.)
It can be produced by adding allyl alcohol to the (substituted) cyclopentadiene dimer represented by Typical compounds of the monomer (a) include compounds of the following structural formula (I-1) or (I-2).

[0013]

[Chemical 4]

As the monomer component (a) of the copolymer of the present invention, different two compounds represented by the above general formula (I) are used.
One or more monomers may be used as a mixture. on the other hand,
The monomer (b) in the present invention has an α-olefin having 6 to 20 carbon atoms and / or an alkyl group having 2 carbon atoms.
~ 20 alkyl vinyl ethers. The α-olefin is a straight-chain or low-branch hydrocarbon having a carbon-carbon double bond at its terminal, and specifically, those obtained by low-polymerizing ethylene are preferably used. Is used by separating an α-olefin having a desired carbon number from the reaction product by means such as distillation. In the present invention, the α-olefin having 6 to 20 carbon atoms is not limited to a single α-olefin and may be used as a mixture thereof. When the carbon number of the α-olefin exceeds 20, the resulting copolymer becomes solid at room temperature, which is not preferable. When it is less than 6, complicated operations such as reaction under pressure during synthesis of the copolymer are required. It is not preferable because it is necessary.

The alkyl vinyl ether is an alkyl vinyl ether having an alkyl group having a straight chain or a branched chain having 2 to 20 carbon atoms.
Ethyl vinyl ether, propyl vinyl ether,
Isopropyl vinyl ether, butyl vinyl ether, isobutyl vinyl ether, sec-butyl vinyl ether, cyclohexyl vinyl ether, hexyl vinyl ether, 2-ethylhexyl vinyl ether, octyl vinyl ether, lauryl vinyl ether, myristyl vinyl ether, palmityl vinyl ether, stearyl Vinyl ether and the like are preferably used. In the present invention, the alkyl vinyl ether having 2 to 20 carbon atoms may be used alone or as a mixture thereof. When the number of carbon atoms of the alkyl group of the alkyl vinyl ether exceeds 20, the resulting copolymer becomes a solid at room temperature, which is not preferable, and when it is less than 2, complicated reactions such as reaction under pressure during synthesis of the copolymer are required. It is not preferable because it requires various operations. The carbon number of the alkyl group of the alkyl vinyl ether is preferably 6 to
Eighteen.

The copolymer of the present invention is a copolymer in which the monomer (a) and the monomer (b) are essential raw materials, and contains 20 to 98 mol% of units derived from the monomer (a), and the monomer. 2 to 50 mol% of the unit derived from (b)
contains. Among them, the unit derived from the monomer (a) and the unit derived from the monomer (b) are each 3
It is preferable to contain 0 to 90 mol% and 5 to 40 mol%.

Within this range, the copolymer of the present invention has a monomer (a) having a large specific gravity and a monomer (b) having a small specific gravity.
The specific gravity can be adjusted in a wide range by adjusting the copolymerization molar ratio and the carbon number of each monomer.
Therefore, in order to use the copolymer of the present invention as a blood separating agent, the copolymerization molar ratio and the carbon number of the monomer may be adjusted so as to obtain a desired specific gravity.

The copolymer of the present invention is derived from a monomer (c) having an ethylenically unsaturated bond copolymerizable therewith, in addition to the units derived from the monomers (a) and (b). It is also possible to contain such units in the copolymer in an amount of 0 to 30 mol%, preferably 0 to 20 mol%. Examples of the monomer (c) include the above (a) and (b)
It is not particularly limited as long as it is a compound having an ethylenically unsaturated bond other than the monomer (1), but examples of the compound having one ethylenically unsaturated bond include 1,2-epoxydecene-9 and about 2 to 20 carbon atoms. Alkyl allyl ether having an alkyl group, norbornene and the like.
As the monomer (c), a monomer that does not have a highly polar group such as an ester group or an amide group is particularly preferable.

The copolymer of the present invention can be obtained by copolymerizing the above-mentioned monomers (a) and (b) and, if necessary, the monomer (c) at a desired polymerization ratio. Various methods can be applied as the polymerization method, but radical polymerization is preferably used. Specifically, for example, a method in which the monomers (a) and (b) and optionally the monomer (c) are charged all at once in a reactor and a radical polymerization initiator is continuously or dividedly added to carry out radical polymerization is known. Can be mentioned.
The polymerization reaction is usually about 60 to 200 ° C., preferably 80.
Performed at ~ 190 ° C. Examples of the radical polymerization initiator include peroxides such as di-t-butylperoxide, t-butylperoxyoctoate, t-butylperoxyisopropyl carbonate, t-butylperoxybenzoate, and dicumyl peroxide. The number average molecular weight of the obtained copolymer is usually 500.
It is about 10,000. Moreover, the viscosity is 1,000 to
It is about 1,500,000 cP.

The polymerization is preferably a solution polymerization method or a solventless (bulk) polymerization method, but is not limited thereto. Examples of the solvent in the solution polymerization method include xylene, diisopropylbenzene, mesitylene, toluene and benzene. The desired copolymer can be easily obtained by separating the solvent from the reaction mixture by distillation after the completion of the polymerization reaction. On the other hand, in order to improve productivity, a copolymerization method without a solvent is advantageous. The molecular weight can be adjusted easily by using a radical chain transfer agent or a chain transfer solvent together or adjusting the polymerization temperature.

The copolymer of the present invention may be further hydrogenated after the copolymerization reaction. Hydrogenation tends to improve the hue of the copolymer and increase the chemical stability of the copolymer. The copolymer of the present invention is particularly useful as a blood separating agent used for separating components in blood. In this case, from the viewpoint of the specific gravity of each blood component to be separated or the separation operation, the temperature of the copolymer is 25 ° C.
Has a specific gravity of 1.00 to 1.08, preferably 1.0
28 to 1.060 and a viscosity of 1,000 to 1,
500,000 cP, preferably 10,000-40
Those in the range of 10,000 cP are preferably used.
If the viscosity is too low, the storage stability of the resulting separating agent is poor, and the separating agent easily moves due to gravity at high temperatures,
It is not preferable because it is difficult to maintain the shape. On the other hand, if the viscosity is too high, there are drawbacks such that handling and dispensing operation to the blood collection tube are not easy due to the high viscosity. In addition, the floatability is insufficiently secured, and the separation performance is deteriorated.

The copolymer of the present invention can be used as it is as a blood separating agent, but it is used as a main component and is used as a blood separating agent for the purpose of adjusting specific gravity or viscosity as necessary. Various additives may be added for the purpose of maintaining the shape. As such a compounding agent,
Examples include inorganic fine powders such as silica, bentonite, titanium oxide, alumina, and talc, and polymer fine powders such as polystyrene powder and polyurethane powder. The mixing ratio thereof is usually 0 with respect to 100 parts by weight of the copolymer of the present invention. ~
It is in the range of 20 parts by weight.

The blood separating agent of the present invention usually preferably contains a gelling agent in order to maintain a stable non-flowing state before and after the centrifugation operation. As a gelling agent,
For example, glutamic acid amide, hydrogenated castor oil, organic gelling agents such as dibenzylidene sorbitol, hydrophobic silica,
An inorganic gelling agent such as an aliphatic amine derivative of smectite clay may be used. The blending ratio of these gelling agents is in the range of 0.1 to 20 parts by weight with respect to 100 parts by weight of the polymer. If the addition amount of the gelling agent is too small, during the blood separation operation, due to the flow of the partition wall formed by the blood separating agent due to insufficient strength of the separating agent,
It may not work well as a separating agent. Further, the shape retention of the separating agent during storage tends to be insufficient, and storage stability tends to be insufficient. On the other hand, when the amount of the gelling agent is too much, the fluidity becomes insufficient, so that it is difficult to secure the floatability of the separating agent during the centrifugal separation operation or the fluidity of the separating agent is insufficient, and the separation function Deterioration occurs.

The blood separating agent of the present invention is required to have a specific gravity intermediate between serum components and blood clot components or plasma components and blood cell components. Therefore, the specific gravity at 25 ° C. is 1.
It is preferably in the range of 028 to 1.060. For example, in the case of a blood separation tube containing a blood separation agent at the bottom, the greater the difference in specific gravity between the blood clot component or blood cell component and the blood separation agent, the greater the floatability of the separation agent during centrifugation, which is preferable. When the specific gravity is less than 1.028, a part of the separating agent having a small specific gravity may be separated in the serum or plasma component after centrifugation, which is not preferable.

The blood separating agent of the present invention containing the copolymer of the present invention is pale yellow, transparent and odorless, and is particularly inert to blood. That is, there is no risk of causing phenomena such as blood adsorption and elution, it does not contain volatile components, and it is stable over time. In addition, since the polarity is low, the adsorption and solubility of the drug contained in serum are low, the measured value of the drug is not adversely affected, and a more accurate test value can be obtained. The blood separating agent of the present invention is generally stored in the bottom of a vacuum or non-vacuum blood collection tube in advance and used.

Although the case where the copolymer of the present invention is used as a blood separating agent has been described above, the copolymer of the present invention can be used as it is or as a mixture with various substances for various other purposes.

[0027]

EXAMPLES Next, the present invention will be described in more detail by way of examples, but the present invention is not limited to the following examples without departing from the gist thereof.

Synthesis Example 1 (Production of allyl ether compound) In a 2-liter flask, dicyclopentadiene 400 was added.
g and 600 g of allyl alcohol were charged and mixed. Boron trifluoride etherate (BF ₃ · Et) was added to the mixture.
₂ O) 50 g was gradually added. Then, the mixture was heated and reacted under reflux (about 100 ° C.) for 4 hours. Then, the reaction solution was cooled, 300 cc of toluene was added, and an alkaline aqueous solution was further added to this to wash and remove unreacted allyl alcohol and the catalyst. Then, it is distilled under reduced pressure to give a liquid dicyclopentadiene allyl alcohol adduct 5
00g (specific gravity d ₄ ²⁵ 0.996) was obtained.

Synthesis Example 2 (Production of Allyl Ether Compound) A 2 liter flask was charged with 480 g of methylcyclopentadiene dimer and 348 g of allyl alcohol and mixed. Boron trifluoride etherate (B
F3.Et2O) 50 g was gradually added. Then, the mixture was heated and reacted under reflux (about 100 ° C.) for 4 hours. Then, the reaction solution was cooled, 300 cc of toluene was added, and an alkaline aqueous solution was further added to this to wash and remove unreacted allyl alcohol and the catalyst. Then, the mixture was distilled under reduced pressure to give 382 g of an allyl alcohol adduct of liquid methylcyclopentadiene dimer (specific gravity d ₄ ²⁵ 0.96
6) was obtained.

Example 1 (Production of Copolymer) In a 1-liter flask, 240 g of an allyl alcohol adduct of dicyclopentadiene produced in Synthesis Example 1 and an α-olefin having 12 to 14 carbon atoms (trade name: dialene 12).
4, 60 g of Mitsubishi Kasei Co., Ltd. and 225 g of diisopropylbenzene were charged in a batch, and under a nitrogen atmosphere, 18
After heating to 0 ° C., 54 g of di-t-butyl peroxide was added thereto over 12 hours while maintaining the temperature, to carry out a copolymerization reaction. After completion of the reaction, under reduced pressure (6 mmH
The light boiling components and unreacted monomers contained in the reaction mixture were distilled off at 160 ° C. to obtain 135 g of a copolymer. The obtained copolymer was pale yellow and transparent and had a viscosity at 25 ° C. of 136,400 cP, a specific gravity of d ₄ ²⁵ 1.030, and a number average molecular weight (measured by gel permeation chromatography and converted into polystyrene). Was 650.

Example 2 (Production of Copolymer) A 1-liter flask was charged with 162 g of an allyl alcohol adduct of dicyclopentadiene produced in Synthesis Example 1 and 75 g of dodecyl vinyl ether all at once, and the mixture was placed under a nitrogen atmosphere at 180 ° C. Then, 21 g of di-t-butyl peroxide was added thereto over 6 hours while maintaining the temperature, to carry out a copolymerization reaction. After completion of the reaction, the light-boiling components and unreacted monomers contained in the reaction mixture were distilled off at 160 ° C. under reduced pressure (6 mmHg) to obtain 135 g of a copolymer. The obtained copolymer was pale yellow and transparent and had a viscosity of 126,000 cP at 25 ° C. and a specific gravity of d ₄ ²⁵ 1.
031, number average molecular weight (measured by gel permeation chromatography and converted into polystyrene)
Was 1,100.

Example 3 (Production of Copolymer) Allyl alcohol adduct 1 of methylcyclopentadiene dimer produced in Synthesis Example 2 was placed in a 500 cc flask.
80 g, 10 g of α-olefin having 12 to 14 carbon atoms (trade name Dialen 124, registered trademark of Mitsubishi Kasei Co., Ltd.) and 150 g of diisopropylbenzene were charged all at once and heated to 180 ° C. under a nitrogen atmosphere. While maintaining the temperature, 25 g of di-t-butyl peroxide was added over 12 hours to carry out a copolymerization reaction. After completion of the reaction, the light-boiling components and unreacted monomers contained in the reaction mixture were distilled off at 160 ° C. under reduced pressure (6 mmHg) to obtain 110 g of a copolymer. The obtained copolymer was pale yellow and transparent, had a viscosity of 162,000 cP at 25 ° C. and a specific gravity of d ₄ ²⁵ 1.
034, number average molecular weight (measured by gel permeation chromatography and converted into polystyrene)
Was 700.

Example 4 (Production of Copolymer) Allyl alcohol adduct 1 of methylcyclopentadiene dimer produced in Synthesis Example 2 was placed in a 500 cc flask.
90 g, 10 g of dodecyl vinyl ether and 50 g of diisopropylbenzene were charged all at once under a nitrogen atmosphere 18
After heating to 0 ° C., 20 g of di-t-butyl peroxide was added thereto over 10 hours while maintaining the temperature, to carry out a copolymerization reaction. After completion of the reaction, under reduced pressure (6 mmHg)
At 160 ° C., the light boiling components and unreacted monomers contained in the reaction mixture were distilled off to obtain 130 g of a copolymer. The obtained copolymer is pale yellow and transparent and has a viscosity of 1 at 25 ° C.
It had a specific gravity of d ₄ ²⁵ 1.029 and a number average molecular weight (measured by gel permeation chromatography and converted into polystyrene) of 620.

Comparative Example 1 (Production of Acrylic Polymer) 240 g of toluene was charged into a 1 liter flask and heated to 100 to 110 ° C. under a nitrogen atmosphere, and then butyl acrylate 36 was added thereto while keeping the temperature.
A mixture of 0 g and t-butylperoxyoctoate (3.6 g) was added over 5 hours, and after the addition, aging was carried out at the same temperature for 2 hours. After completion of the reaction, toluene and unreacted monomers were distilled off under reduced pressure (6 mmHg) to give an acrylic polymer 3
57 g were obtained. The polymer obtained is pale yellow and transparent at 25 ° C.
At a viscosity of 65,000 cP and a specific gravity of d ₄ ²⁵ 1.
It was 042.

Test Example 1 (Evaluation of Drug Adsorption) Each polymer obtained in Examples 1 to 4 and Comparative Example 1 was evaluated by the following method. About 1.5 g of each polymer was put into a test tube having a constant diameter, 1 cc of bovine serum containing a drug at a constant concentration was added thereto, and the mixture was allowed to stand at 25 ° C. After 72 hours, only bovine serum was collected and the amount of drugs (phenytoin and lidocaine) contained therein was measured by the fluorescent immuno-antibody method. The ratio of the drug concentration in the bovine serum after being left for 72 hours to the drug concentration in the original bovine serum was determined and defined as the drug residual rate. Evaluation is ○, 70-80% when the drug residual rate is 80% or more.
Was designated as Δ, and 70% or less was designated as x. The results are shown in Table-1. For comparison, a separating agent A (a silicon-based material gelled with silica particles) and a separating agent B (a polyester-based material, which is a silica-based particle) are commercially available as serum separating agents. And a cyclopentadiene oligomer ECR-327 (trade name, specific gravity d ₄ manufactured by Tonex Co., Ltd.).
²⁵ 1.036, viscosity 168,000 cP / 25 ° C., number average molecular weight 220, thermal polymerized product of cyclopentadiene) and similar evaluation was performed.

[0036]

[Table 1]

Test Example 2 (Evaluation of Volatile Components) The contents of volatile components of the polymers of Examples 1 to 4 and Comparative Examples 1 and 2 were measured by the following method. Take 100 g of the polymer in a flask and heat it to 150 ° C. under a nitrogen atmosphere to give a pressure of 6 mmH.
The volatile matter was distilled off under reduced pressure of g, and the weight% of the distillate was calculated. The results are shown in Table-2.

[0038]

[Table 2] Although the copolymers of Examples 1 to 4 and the polymer of Comparative Example 1 do not contain a volatile component, the cyclopentadiene oligomer of Comparative Example 2 contains a volatile component. Examples 5 to 6 (Production of Separating Agent) 100 parts by weight of the copolymer obtained in Example 1, 2 parts by weight of Aerosil R-972D (hydrophobic silica fine powder, manufactured by Nippon Aerosil Co., Ltd.) and Benton 34 (smectite clay). 2 parts by weight of the aliphatic amine derivative of (manufactured by NL Industry Co., Ltd.) was thoroughly kneaded with a three-roll mill to produce a blood separating agent (Example 5).

Similarly, the copolymer 100 obtained in Example 2 was used.
Parts by weight, Aerosil R-972D4 parts by weight and SH-3
The blood separating agent was produced in an amount of 0.5 part by weight of 771 (dimethylpolysiloxane-polyoxyalkylene copolymer, manufactured by Toray Silicone Co., Ltd.) (Example 6). Each of these blood separating agents had an appropriate thixotropic property, showed fluidity by applying a stress such as a centrifugal force, and formed a gel in a normal standing state. Test Example 3 (serum separation test) About 1.5 g of each blood separating agent prepared in Examples 5 and 6 was used as 1
The sample was placed in the bottom of a 0 cc blood collection tube, and the whole blood sample collected was placed and left to stand. After blood coagulation proceeded and the blood was separated into serum and blood clot, centrifugation was performed at 3000 rpm for 10 minutes, and a gel of the blood separation agent was formed between the blood serum and the blood clot for any of the blood separation agents. Serum could be easily removed from the blood collection tube by decantation.

[0040]

EFFECT OF THE INVENTION Since the copolymer of the present invention is a hydrocarbon-based polymer, it does not cause any physical or chemical change when used as a blood separating agent, and can be used as a component to be measured during blood separation operation. It is particularly advantageous as a blood separating agent for a vacuum blood collection tube because it hardly changes with time and contains almost no volatile component, and is extremely useful in practice.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mariko Kimura 1000 Kamoshida-cho, Midori-ku, Yokohama-shi, Kanagawa Sanryo Kasei Co., Ltd.

Claims (1)

[Claims] 1. The following general formula (I): (In the formula, R represents a lower alkyl group, and n represents 0 or 1.) A unit derived from the monomer (a) represented by 20 to 98 mol%, an α-olefin having 6 to 20 carbon atoms, and / or Alternatively, it has a unit of 2 to 50 mol% derived from an alkyl vinyl ether (b) having an alkyl group having 2 to 20 carbon atoms, and a copolymerizable ethylenically unsaturated bond other than the above (a) and (b). A number average molecular weight of 50 containing 0 to 30 mol% of units derived from the monomer (c)
0-10,000 allyl ether compound-based copolymer. 2. The copolymer according to claim 1, which is obtained by copolymerization in the presence of a radical polymerization initiator. 3. A blood separating agent containing the allyl ether compound-based copolymer according to claim 1 or 2 as a main component.