JPH05140217A - Purification of polyvinylaromatic acetal - Google Patents

Purification of polyvinylaromatic acetal

Info

Publication number
JPH05140217A
JPH05140217A JP30799991A JP30799991A JPH05140217A JP H05140217 A JPH05140217 A JP H05140217A JP 30799991 A JP30799991 A JP 30799991A JP 30799991 A JP30799991 A JP 30799991A JP H05140217 A JPH05140217 A JP H05140217A
Authority
JP
Japan
Prior art keywords
lower layer
pvaa
added
solution
alcohol
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP30799991A
Other languages
Japanese (ja)
Other versions
JP3094583B2 (en
Inventor
Toshikazu Ishii
利和 石井
Tomoyuki Mori
知行 森
Noboru Haji
登 土師
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mitsubishi Kasei Corp
Original Assignee
Mitsubishi Kasei Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Mitsubishi Kasei Corp filed Critical Mitsubishi Kasei Corp
Priority to JP03307999A priority Critical patent/JP3094583B2/en
Publication of JPH05140217A publication Critical patent/JPH05140217A/en
Application granted granted Critical
Publication of JP3094583B2 publication Critical patent/JP3094583B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Landscapes

  • Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)

Abstract

PURPOSE:To obtain a highly pure product stably without causing scale deposition on the wall, etc., of a reactor. CONSTITUTION:The objective process comprises adding 0.7-4 pts.wt., per pt.wt. reaction solution, 1-3C alcohol to a reaction solution containing a polyvinylaromatic acetal (hereinbelow referred to as PVAA) obtained by reacting polyvinyl alcohol with an aromatic aldehyde or a mixture thereof with and aliphatic aldehyde in an aromatic hydrocarbon solvent under agitation to separate PVAA as a flowable lower layer, removing the upper layer, adding 1-4 pts.wt., per pt.wt. lower layer, aromatic hydrocarbon solvent to the lower layer containing PVAA to form a solution, adding 0.7-5 pts.wt., per pt.wt. obtained solution, 1-3C alcohol to the obtained solution under agitation to separate PVAA as a flowable lower layer, and removing the upper layer.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明はポリビニル芳香族アセタ
ールの精製方法に関する。詳しくは本発明は芳香族炭化
水素溶媒中でポリビニルアルコールと芳香族アルデヒド
とを反応させることによって得られたポリビニル芳香族
アセタールを精製する方法に関する。
FIELD OF THE INVENTION The present invention relates to a method for purifying polyvinyl aromatic acetals. More specifically, the present invention relates to a method for purifying a polyvinyl aromatic acetal obtained by reacting polyvinyl alcohol with an aromatic aldehyde in an aromatic hydrocarbon solvent.

【0002】[0002]

【従来の技術】ポリビニルアルコールとアルデヒドとの
縮合反応によって得られるポリビニルアセタールはアル
デヒド原料の選択によって種々の物性を有し塗料、膜
材、シート等の用途に用いられる。ポリビニルアルコー
ルをアセタール化する方法は種々知られており代表的な
ものとして ポリビニルアルコールの水溶液から出発して反応の
進行と共にアセタール化物を沈殿析出させる方法(「沈
殿法」) アセタール化物の溶媒中にポリビニルアルコールを
分散させたものから出発して反応の進行と共に均一溶液
を得る方法(「溶解法」) 等が知られている。
2. Description of the Related Art Polyvinyl acetal obtained by condensation reaction of polyvinyl alcohol and aldehyde has various physical properties depending on the selection of aldehyde raw material and is used for coatings, film materials, sheets and the like. Various methods of acetalizing polyvinyl alcohol are known, and as a typical method, a method of starting an aqueous solution of polyvinyl alcohol and precipitating an acetal compound as the reaction progresses (“precipitation method”) Polyvinyl alcohol in a solvent of the acetal compound A method is known in which a homogeneous solution is obtained as the reaction progresses, starting from a dispersion of alcohol (“dissolution method”).

【0003】アセタール化方法の選択はアルデヒドの種
類、生成物の用途等に依存しそれぞれ得失を有するがこ
れらに共通する重要な技術的課題は生成したアセタール
化物の精製方法である。上記の溶解法によってポリビニ
ル芳香族アセタール(以下PVAAという)を製造する
にはトルエン等の芳香族炭化水素溶媒中でポリビニルア
ルコールと芳香族アルデヒドとを反応させ反応の進行に
伴って生成するPVAAを溶媒中に溶解させ、必要によ
り反応終了後に反応液を濾過することによってPVAA
を含む反応液が得られる。上記のPVAAを含む反応液
からPVAAを取得するには通常PVAAの非溶剤中に
PVAA溶液を加えてPVAAを析出させる方法が採用
されている。こうした方法が採用される主な理由として
は、非溶剤中にPVAAの溶液を加える方法は一般に精
製度の高いPVAAが得られ易いためである。
The selection of the acetalization method depends on the type of aldehyde, the use of the product, and the like, and each has its advantages and disadvantages. An important technical problem common to these is a method for purifying the acetalized product. In order to produce a polyvinyl aromatic acetal (hereinafter referred to as PVAA) by the above-mentioned dissolution method, polyvinyl alcohol and an aromatic aldehyde are reacted in an aromatic hydrocarbon solvent such as toluene, and PVAA produced as the reaction proceeds is a solvent. PVAA by dissolving it in the reaction solution and filtering the reaction solution after completion of the reaction if necessary.
A reaction solution containing is obtained. In order to obtain PVAA from the above reaction solution containing PVAA, a method of precipitating PVAA by adding a PVAA solution to a non-solvent of PVAA is usually employed. The main reason for adopting such a method is that a method of adding a solution of PVAA in a non-solvent generally makes it easy to obtain highly purified PVAA.

【0004】[0004]

【発明が解決しようとする課題】しかるに前記の、非溶
剤のメタノールの中に攪拌しながらPVAAを含む反応
液を加えPVAAを析出する方法においてはPVAAは
モチ状又はゴム状となり易く、流動性がなくかつ次第に
大きくブロック化するほか攪拌翼又は器壁等に付着しや
すいため、攪拌機の異常振動、停止等の問題が発生しス
ケールアップをした状態では安定運転できなかった。こ
のため攪拌機は通常より強力な攪拌振動を有することが
必要であるほか、場合によっては装置の破損にも対応し
なければならず、工業的生産は非常に困難であった。
However, in the above-described method of precipitating PVAA by adding the reaction solution containing PVAA to methanol as a non-solvent while stirring, PVAA tends to be sticky or rubbery, and has poor fluidity. Since it did not exist and gradually formed into large blocks and easily adhered to the stirring blades or vessel walls, problems such as abnormal vibration and stoppage of the stirrer occurred, and stable operation could not be performed in a scale-up state. For this reason, the stirrer is required to have a stronger stirring vibration than usual, and in some cases, it is necessary to cope with damage to the device, which makes industrial production very difficult.

【0005】[0005]

【課題を解決するための手段】本発明者らは上記の問題
点を解決すべく鋭意検討を重ねた結果PVAA溶液中に
非溶剤を加える方法を特定の条件で実施することにより
上記の問題点が解決されかつ精製度の高いPVAAが得
られることを見出して本発明を完成するに至った。
Means for Solving the Problems The inventors of the present invention have made extensive studies to solve the above-mentioned problems, and as a result, the above-mentioned problems can be solved by carrying out a method of adding a non-solvent into a PVAA solution under specific conditions. The present invention has been completed by finding that PVAA having a high degree of purification can be obtained.

【0006】即ち、本発明の要旨は、芳香族炭化水素溶
媒中でポリビニルアルコールと芳香族アルデヒド、又は
芳香族アルデヒド及び脂肪族アルデヒドとを反応させる
ことによって得られたポリビニル芳香族アセタール(以
下PVAAという)を含む反応液に、該反応液の0.7
〜4倍重量の炭素数1〜3のアルコール(以下、C1
3 アルコールという)を攪拌しながら加えてPVAA
を流動性のある下層として分離させ、上層の溶媒相を除
去し、次いで得られたPVAAを含む下層に芳香族炭化
水素溶媒を下層に対し1〜4倍重量加えて溶解し、この
得られた溶液に対し0.7〜4倍重量のC1 〜C3 アル
コールを攪拌しながら加えてPVAAを流動性のある下
層として分離させ、上層の溶媒相を除去することを特徴
とするPVAAの精製方法に存する。
That is, the gist of the present invention is to provide a polyvinyl aromatic acetal (hereinafter referred to as PVAA) obtained by reacting polyvinyl alcohol with an aromatic aldehyde or an aromatic aldehyde and an aliphatic aldehyde in an aromatic hydrocarbon solvent. ) Is added to the reaction solution containing 0.7% of the reaction solution.
~ 4 times the weight of alcohol having 1 to 3 carbon atoms (hereinafter, C 1 ~
C 3 PvaA a) of the alcohol was added with stirring
Was separated as a fluid lower layer, the solvent phase of the upper layer was removed, and then the obtained lower layer containing PVAA was dissolved by adding an aromatic hydrocarbon solvent in an amount of 1 to 4 times the weight of the lower layer. A method for purifying PVAA, which comprises adding 0.7 to 4 times the weight of C 1 to C 3 alcohol to the solution with stirring to separate PVAA as a fluid lower layer and removing the upper solvent phase. Exist in.

【0007】以下、本発明につき詳細に説明する。本発
明で用いられる芳香族アルデヒドとしてはベンズアルデ
ヒド類又はフェニルアセトアルデヒドでありベンズアル
デヒド類としてはベンズアルデヒド、メチルベンズアル
デヒド、ブチルベンズアルデヒド、クロロベンズアルデ
ヒドなどが含まれる。
The present invention will be described in detail below. The aromatic aldehyde used in the present invention is benzaldehyde or phenylacetaldehyde, and the benzaldehyde includes benzaldehyde, methylbenzaldehyde, butylbenzaldehyde, chlorobenzaldehyde and the like.

【0008】又、脂肪族アルデヒドとしては炭素数1な
いし4の直鎖状又は分岐鎖状のアルキル基をもつアルデ
ヒドで、アセトアルデヒド、プロピオンアルデヒド、ブ
チルアルデヒドが含まれる。又、C1 〜C3 アルコール
としてはメチルアルコール、エチルアルコール及びプロ
ピルアルコール等が用いられるが、メチルアルコール及
びエチルアルコールが特に好ましい。
The aliphatic aldehyde is an aldehyde having a linear or branched alkyl group having 1 to 4 carbon atoms and includes acetaldehyde, propionaldehyde and butyraldehyde. As C 1 -C 3 alcohols, methyl alcohol, ethyl alcohol, propyl alcohol and the like are used, but methyl alcohol and ethyl alcohol are particularly preferable.

【0009】又、芳香族炭化水素溶媒としてはベンゼ
ン、トルエン、キシレン等が含まれるが、トルエンが特
に好ましい。本発明において反応液からPVAAを分離
する方法としては該反応液を敷液とし、これにC1 〜C
3 のアルコールを該反応液に対し0.7〜4倍重量、好
ましくは0.7〜3倍重量、更に好ましくは1〜2.5
倍重量攪拌しながら添加することによりPVAAは流動
性を有する高粘度の液状相となり下層として分離するこ
とができる。
The aromatic hydrocarbon solvent includes benzene, toluene, xylene and the like, with toluene being particularly preferred. In the present invention, as a method for separating PVAA from the reaction solution, the reaction solution is used as a bed solution, and C 1 to C
0.7 to 4 times by weight, preferably 0.7 to 3 times by weight, more preferably 1 to 2.5 times the weight of the alcohol of 3
By adding double weight while stirring, PVAA becomes a liquid phase having a high viscosity with fluidity and can be separated as a lower layer.

【0010】C1 〜C3 のアルコールの量が少ないとP
VAAの回収率が低下するので好ましくない。又、C1
〜C3 のアルコールの量が多いとPVAAが固くなり処
理操作上好ましくない。このPVAAを含む下層は分離
の過程でモチ状、ゴム状になることはなく流動性を保持
することができる。従って、攪拌翼に固着することなく
通常の攪拌動力の攪拌機でも異常振動、停止等の問題が
発生することなく安定運転が可能である。
If the amount of C 1 -C 3 alcohol is small, P
It is not preferable because the recovery rate of VAA decreases. Also, C 1
If the amount of C 3 -C 3 alcohol is large, PVAA becomes hard, which is not preferable in the processing operation. The lower layer containing PVAA does not become sticky or rubber during the separation process and can maintain fluidity. Therefore, stable operation is possible without causing problems such as abnormal vibration and stop even with a stirrer of ordinary stirring power without sticking to the stirring blade.

【0011】また攪拌を停止するとPVAAは下層とし
て分液するため上層の溶媒層を抜き出すことが容易であ
るほか、下層側を抜出すことも可能である。こうして得
られた下層に存在するPVAAを更に精製するため、上
層を抜き出し下層を残したあと、この下層に対し1〜4
倍重量好ましくは2〜3倍重量の芳香族炭化水素溶媒を
加えて攪拌し溶解してからこれにこの溶液に対し0.7
〜4倍重量好ましくは0.7〜3倍重量、更に好ましく
は1〜2.5倍重量のC1 〜C3 アルコールを攪拌しな
がら加えることによりPVAAを含む流動性を有する液
状相とし下層として再度分離することができる。
When the stirring is stopped, PVAA separates as a lower layer, so that the upper solvent layer can be easily extracted, and the lower layer side can also be extracted. In order to further purify the PVAA present in the lower layer thus obtained, the upper layer was extracted and the lower layer was left.
Double weight, preferably 2 to 3 times the weight of the aromatic hydrocarbon solvent is added, stirred and dissolved, and then 0.7% of this solution is added.
To 4 times by weight, preferably 0.7 to 3 times by weight, and more preferably 1 to 2.5 times by weight of C 1 to C 3 alcohol is added with stirring to form a fluid phase containing PVAA as a lower layer. It can be separated again.

【0012】上記の処理により未反応の芳香アルデヒ
ド、脂肪族アルデヒド、Cl分など不純物が少く精製度
の高いPVAAを得ることができる。又、前記の溶解−
分離処理を2度又はそれ以上の回数繰返すことにより、
更にPVAA純度を向上させることができる。
By the above treatment, it is possible to obtain PVAA having a small amount of impurities such as unreacted aromatic aldehyde, aliphatic aldehyde, and Cl content and a high degree of purification. In addition, the dissolution-
By repeating the separation process twice or more,
Furthermore, the PVAA purity can be improved.

【0013】[0013]

【実施例】以下本発明を実施例により更に詳細に説明す
るが、本発明はその要旨を越えない限り、以下の実施例
に限定されるものではない。 実施例−1 攪拌機付き2リットルフラスコにトルエン600g、フ
ェニルアセトアルデヒド128g、n−ブチルアルデヒ
ド19.4g、ポリビニルアルコール58.4gを仕込
み、混合したのち35%塩酸7.8gを追加し、昇温さ
せ55〜60℃で5時間アセタール化反応をさせた。こ
の反応液263gに酢酸ソーダ3.5gをメタノール1
03gに溶解させた液を加えて中和し、この液を濾過し
て不溶解物を除去した。
EXAMPLES The present invention will be described in more detail with reference to Examples below, but the present invention is not limited to the following Examples unless it exceeds the gist. Example-1 To a 2-liter flask equipped with a stirrer, 600 g of toluene, 128 g of phenylacetaldehyde, 19.4 g of n-butyraldehyde and 58.4 g of polyvinyl alcohol were charged and mixed, and then 7.8 g of 35% hydrochloric acid was added and the temperature was raised to 55. The acetalization reaction was carried out at -60 ° C for 5 hours. To 263 g of this reaction solution, 3.5 g of sodium acetate was added to 1 part of methanol.
A solution dissolved in 03 g was added for neutralization, and this solution was filtered to remove insoluble matter.

【0014】攪拌機及びバッフル付1リットルセパラブ
ルフラスコに中和濾過した反応液365gを敷液として
仕込み、これにメタノール450gを攪拌しながら徐々
に加えていった。この場合メタノールの合計量は中和前
の反応液に対し2.1倍とした。メタノール添加当初は
均一溶液であったが、メタノール添加量が増加していく
と混合液は白濁しポリビニルフェニルアセタール(以下
PVPA)が分離した。
A 1 liter separable flask equipped with a stirrer and a baffle was charged with 365 g of the neutralized and filtered reaction solution as a bed solution, and 450 g of methanol was gradually added thereto with stirring. In this case, the total amount of methanol was 2.1 times the reaction liquid before neutralization. The solution was homogeneous at the beginning of the addition of methanol, but as the amount of addition of methanol increased, the mixed solution became cloudy and polyvinylphenyl acetal (hereinafter referred to as PVPA) separated.

【0015】メタノールを全量添加してもモチ状、ゴム
状のかたまりは認められず、分離したPVPA相は流動
性を保っておりこのため攪拌機の異常振動等の問題はな
く安定運転ができた。攪拌を停止するとPVPA相は高
粘度の液状相として下層に分離した。上層液をフラスコ
上部から吸引抜出したのち下層の量は71gであった。
これにトルエン150g(下層に対し2.1倍)を加え
下層を溶解した。この液中のPVPAは25gであり、
更にこのPVPAに対する未反応フェニルアセトアルデ
ヒドの残存量は9wt%であった。これにメタノール4
40g(トルエン溶液に対し2.0倍)を攪拌しながら
加えていくとPVPAを含む相の分離状況は反応液から
分離した場合と同様の状態となり、PVPAを含む下層
は流動性を有していた。2回目の回収PVPAトルエン
溶液中のPVPAに対するフェニルアセトアルデヒドの
残存量は0.6wt%であった。
No sticky or rubber-like lumps were observed even when the whole amount of methanol was added, and the separated PVPA phase maintained fluidity, and therefore stable operation was possible without abnormal vibration of the stirrer. When the stirring was stopped, the PVPA phase separated into a lower layer as a highly viscous liquid phase. The amount of the lower layer was 71 g after the upper layer liquid was suctioned out from the upper portion of the flask.
To this was added 150 g of toluene (2.1 times the lower layer) to dissolve the lower layer. PVPA in this liquid is 25 g,
Furthermore, the residual amount of unreacted phenylacetaldehyde with respect to this PVPA was 9 wt%. Methanol 4
When 40 g (2.0 times the toluene solution) was added with stirring, the phase separation state of the PVPA-containing phase was the same as when the phase was separated from the reaction liquid, and the lower layer containing PVPA had fluidity. It was The residual amount of phenylacetaldehyde with respect to PVPA in the second recovered PVPA toluene solution was 0.6 wt%.

【0016】実施例−2 実施例−1の反応液52gに酢酸ソーダ0.7gを加え
て中和しこの液を濾過後ビーカーに入れスターラーで攪
拌しながらメタノール42g(反応液に対し0.8倍)
を徐々に添加した。攪拌停止後流動性のある高粘度の液
状相が下層に分離した。上層液を除去したのち下層の量
は14.8gであった。このうちPVPAは3.8gで
ありPVPAに対する未反応フェニルアセトアルデヒド
の残存量は9.2wt%であった。この下層にトルエン
34g(下層に対し2.3倍)を加えて溶解しこれにメ
タノール40g(トルエン溶液に対し0.8倍)を攪拌
しながら加えると流動性のある液状下層が分離した。こ
の下層中のPVPAに対するフェニルアセトアルデヒド
の残存量は0.6wt%であった。
Example-2 0.7 g of sodium acetate was added to 52 g of the reaction solution of Example-1 for neutralization, and this solution was filtered, put in a beaker and stirred with a stirrer to give 42 g of methanol (0.8 to the reaction solution). Times)
Was gradually added. After the stirring was stopped, a fluid high-viscosity liquid phase separated into a lower layer. After removing the upper layer liquid, the amount of the lower layer was 14.8 g. Among them, PVPA was 3.8 g, and the residual amount of unreacted phenylacetaldehyde with respect to PVPA was 9.2 wt%. To this lower layer was added 34 g of toluene (2.3 times that of the lower layer) to dissolve it, and 40 g of methanol (0.8 times that of the toluene solution) was added thereto with stirring to separate a liquid lower layer having fluidity. The residual amount of phenylacetaldehyde with respect to PVPA in this lower layer was 0.6 wt%.

【0017】実施例−3 非溶媒のアルコールとしてエタノールを100g(反応
液に対して1.9倍)使用したほかは実施例−2と同一
条件でテストした結果、下層は流動性のある高粘性液状
相であった。下層の量は13.2gでありこのうちPV
PAは4.8gでPVPAに対する未反応フェニルアセ
トアルデヒド残存量は8.8wt%であった。この下層
にトルエン30g(下層に対し2.3倍)を加えて溶解
しこれにエタノール100g(トルエン溶液に対し2.
3倍)を攪拌しながら加えると流動性のある液状下層が
分離した。この下層中のPVPAに対するフェニルアセ
トアルデヒドの残存量は0.6wt%であった。
Example 3 Tests were conducted under the same conditions as in Example 2 except that 100 g of ethanol was used as the non-solvent alcohol (1.9 times the amount of the reaction solution). As a result, the lower layer was a fluid and highly viscous. It was a liquid phase. The amount of the lower layer is 13.2g, of which PV
PA was 4.8 g, and the amount of unreacted phenylacetaldehyde remaining relative to PVPA was 8.8 wt%. To this lower layer, 30 g of toluene (2.3 times that of the lower layer) was added and dissolved, and 100 g of ethanol was added thereto (2.
(3 times) was added with stirring, and a fluid lower liquid layer was separated. The residual amount of phenylacetaldehyde with respect to PVPA in this lower layer was 0.6 wt%.

【0018】実施例−4 非溶媒のアルコールとしてイソプロパノール100g
(反応液に対し1.9倍)を使用した以外は実施例−2
と同一条件でテストした結果下層は流動性のある高粘性
液状相であった。下層の量は12.6gであり、このう
ちPVPAは3.6gでPVPAに対する未反応フェニ
ルアセトアルデヒドの残存量は8.4wt%であった。
この下層にトルエン27g(下層に対して2.1倍)を
加えて溶解しこれにイソプロパノール87g(トルエン
溶液に対し2.2倍)を攪拌しながら加え流動性のある
液状下層が分離した。この下層中のPVPAに対するフ
ェニルアセトアルデヒドの残存量は0.5wt%であっ
た。
Example 4 100 g of isopropanol as a non-solvent alcohol
Example-2 except that (1.9 times the reaction liquid) was used.
As a result of testing under the same conditions as above, the lower layer was a fluid and highly viscous liquid phase. The amount of the lower layer was 12.6 g, of which PVPA was 3.6 g, and the residual amount of unreacted phenylacetaldehyde with respect to PVPA was 8.4 wt%.
To this lower layer, 27 g of toluene (2.1 times that of the lower layer) was added and dissolved, and 87 g of isopropanol (2.2 times that of the toluene solution) was added thereto with stirring, and a fluid lower layer was separated. The residual amount of phenylacetaldehyde with respect to PVPA in this lower layer was 0.5 wt%.

【0019】実施例−5 非溶媒のアルコールとしてn−プロパノール100g
(反応液に対して1.9倍)を使用した以外は実施例−
2と同一条件でテストした結果下層は流動性のある高粘
性液状相であったが6.1gと減少していた。下層のう
ちPVPAは2.3gでPVPAに対する未反応フェニ
ルアセトアルデヒドの残存量は7.9wt%であった。
この下層にトルエン14g(下層に対し2.3倍)を加
えて溶解しこれにn−プロパノール46g(トルエン溶
液に対し2.3倍)を攪拌しながら加え流動性のある液
状下層が分離した。この下層中のPVPAに対するフェ
ニルアセトアルデヒドの残存量は0.5wt%であっ
た。
Example 5 100 g of n-propanol as a non-solvent alcohol
Example- (except for using 1.9 times the reaction solution)
As a result of testing under the same conditions as in 2, the lower layer was a highly viscous liquid phase having fluidity, but the amount decreased to 6.1 g. In the lower layer, PVPA was 2.3 g, and the residual amount of unreacted phenylacetaldehyde with respect to PVPA was 7.9 wt%.
To this lower layer, 14 g of toluene (2.3 times that of the lower layer) was added and dissolved, and 46 g of n-propanol (2.3 times that of the toluene solution) was added thereto with stirring, and a liquid lower layer having fluidity was separated. The residual amount of phenylacetaldehyde with respect to PVPA in this lower layer was 0.5 wt%.

【0020】実施例−6 アセタール化反応の原料アルデヒドとしてフェニルアセ
トアルデヒドだけを使用した以外は実施例−1と同一条
件でテストした。その結果1回目の分液下層は流動性の
ある高粘性液状相で下層量として63gであった。この
うちPVPAは23gでPVPAに対する未反応フェニ
ルアセトアルデヒドの残存量は9.2wt%であった。
これにトルエン140g(下層量に対し2.2倍)を加
え下層を溶解しこれにメタノール410g(トルエン溶
液に対し2.0倍)を攪拌しながら加えて流動性のある
下層を得た。この下層中のPVPAに対するフェニルア
セトアルデヒドの残存量は0.6wt%であった。
Example 6 A test was conducted under the same conditions as in Example 1 except that only phenylacetaldehyde was used as the starting aldehyde for the acetalization reaction. As a result, the first liquid separation lower layer was a highly viscous liquid phase having fluidity, and the lower layer amount was 63 g. Among them, PVPA was 23 g, and the residual amount of unreacted phenylacetaldehyde with respect to PVPA was 9.2 wt%.
To this was added 140 g of toluene (2.2 times the amount of the lower layer) to dissolve the lower layer, and 410 g of methanol (2.0 times the amount of the toluene solution) was added to this while stirring to obtain a fluid lower layer. The residual amount of phenylacetaldehyde with respect to PVPA in this lower layer was 0.6 wt%.

【0021】比較例 実施例−1で調製したアセタール化反応液263gに酢
酸ソーダ3.5gをメタノール103gに溶解させた液
を加えて中和し、この液を濾過して不溶解物を除去し
た。攪拌機及びバッフル付1リットルセパラブルフラス
コにメタノール450gを敷液として仕込みこれに中
和、濾過した反応液365gを攪拌しながら加えたが、
反応液添加と同時にPVPAがモチ状に析出し攪拌翼、
バッフル及び器壁に付着した。析出したPVPAは次第
にブロック化しゴム状になり攪拌機が停止することがあ
った。反応液の添加終了後フラスコ上部よりフレキシブ
ルチューブをそう入し液相を吸引抜出しした。析出物の
量は45gであり、これにトルエン113g(析出物に
対し2.5倍)を加えフラスコを傾けてフラスコ内に付
着している固形物をトルエンに接触させて溶解させトル
エン溶液として回収した。
Comparative Example A solution prepared by dissolving 3.5 g of sodium acetate in 103 g of methanol was added to 263 g of the acetalization reaction solution prepared in Example 1 for neutralization, and this solution was filtered to remove insoluble matter. .. A 1 liter separable flask equipped with a stirrer and a baffle was charged with 450 g of methanol as a bed liquid, and to this was added 365 g of the reaction liquid which had been neutralized and filtered with stirring.
At the same time as the reaction solution was added, PVPA was deposited in a sticky shape, and a stirring blade,
It adhered to the baffle and the vessel wall. The deposited PVPA gradually became a block and became rubber-like, and the stirrer sometimes stopped. After the addition of the reaction solution was completed, a flexible tube was inserted from the top of the flask and the liquid phase was sucked out. The amount of the deposit was 45 g, and 113 g of toluene (2.5 times the deposit) was added to this, and the solid substance adhering to the inside of the flask was brought into contact with toluene to dissolve it and recovered as a toluene solution. did.

【0022】この液中のPVPAは26gであり更にこ
のPVPAに対するフェニルアセトアルデヒドの残存量
は6.7wt%であった。更に同フラスコにメタノール
350g(トルエン溶液に対し2.2倍)を仕込み先に
回収したPVPAトルエン溶液を攪拌しながら加えた。
PVPAの析出状況は反応液から実施した場合と同様で
ありブロック化したPVPAにより攪拌機が停止するこ
とがあった。2回目の回収PVPAトルエン溶液中のP
VPAに対するフェニルアセトアルデヒドの残存量は
0.4wt%であった。
The amount of PVPA in this liquid was 26 g, and the residual amount of phenylacetaldehyde with respect to this PVPA was 6.7 wt%. Further, 350 g of methanol (2.2 times the amount of the toluene solution) was charged into the same flask, and the PVPA toluene solution which had been collected at the destination was added while stirring.
The precipitation of PVPA was the same as when it was carried out from the reaction solution, and the stirrer was sometimes stopped by the blocked PVPA. 2nd recovery PVPA P in toluene solution
The residual amount of phenylacetaldehyde relative to VPA was 0.4 wt%.

【0023】[0023]

【発明の効果】本発明によれば、PVAAは流動性のあ
る相として下層に分離され取扱いが極めて容易であるた
め、分離及び溶解分離処理操作(液状相分離処理)を繰
返しても、これらの操作は非常に簡単に実施でき工業的
に有利な精製処理を行なうことができる。又、これらの
操作において、器壁等に付着がなく、安定運転が可能で
ある。更に又精製度の高い製品が得られる。従って本発
明により、PVAAを含む反応溶液からのPVAAの分
離精製が容易にかつ経済的に達成できる。
INDUSTRIAL APPLICABILITY According to the present invention, since PVAA is separated into the lower layer as a fluid phase and is extremely easy to handle, even if the separation and dissolution separation treatment operations (liquid phase separation treatment) are repeated, these The operation is very simple and an industrially advantageous refining process can be performed. Further, in these operations, there is no adhesion on the vessel wall and the like, and stable operation is possible. Furthermore, a highly purified product can be obtained. Therefore, according to the present invention, the separation and purification of PVAA from the reaction solution containing PVAA can be achieved easily and economically.

Claims (1)

【特許請求の範囲】[Claims] 【請求項1】 芳香族炭化水素溶媒中でポリビニルアル
コールと芳香族アルデヒド、又は芳香族アルデヒド及び
脂肪族アルデヒドとを反応させることによって得られた
ポリビニル芳香族アセタール(以下PVAAという)を
含む反応液に、該反応液の0.7〜4倍重量の炭素数1
〜3のアルコール(以下、C1 〜C3 アルコールとい
う)を攪拌しながら加えてPVAAを流動性のある下層
として分離させ、上層の溶媒相を除去し、次いで得られ
たPVAAを含む下層に芳香族炭化水素溶媒を下層に対
し1〜4倍重量加えて溶解し、この得られた溶液に対し
0.7〜4倍重量のC1 〜C3 アルコールを攪拌しなが
ら加えてPVAAを流動性のある下層として分離させ、
上層の溶媒相を除去することを特徴とするPVAAの精
製方法。
1. A reaction liquid containing a polyvinyl aromatic acetal (hereinafter referred to as PVAA) obtained by reacting polyvinyl alcohol with an aromatic aldehyde, or an aromatic aldehyde and an aliphatic aldehyde in an aromatic hydrocarbon solvent. , 0.7 to 4 times the weight of the reaction solution with 1 carbon number
~ 3 alcohols (hereinafter referred to as C 1 -C 3 alcohols) are added with stirring to separate PVAA as a fluid lower layer, the upper solvent phase is removed, and then the resulting lower layer containing PVAA is aromatized. A group hydrocarbon solvent is added to the lower layer in an amount of 1 to 4 times by weight to dissolve the solvent, and 0.7 to 4 times by weight of a C 1 to C 3 alcohol is added to the obtained solution with stirring to add PVAA to the liquid phase. As a lower layer,
A method for purifying PVAA, which comprises removing an upper solvent phase.
JP03307999A 1991-11-22 1991-11-22 Purification method of polyvinyl aromatic acetal Expired - Fee Related JP3094583B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP03307999A JP3094583B2 (en) 1991-11-22 1991-11-22 Purification method of polyvinyl aromatic acetal

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP03307999A JP3094583B2 (en) 1991-11-22 1991-11-22 Purification method of polyvinyl aromatic acetal

Publications (2)

Publication Number Publication Date
JPH05140217A true JPH05140217A (en) 1993-06-08
JP3094583B2 JP3094583B2 (en) 2000-10-03

Family

ID=17975686

Family Applications (1)

Application Number Title Priority Date Filing Date
JP03307999A Expired - Fee Related JP3094583B2 (en) 1991-11-22 1991-11-22 Purification method of polyvinyl aromatic acetal

Country Status (1)

Country Link
JP (1) JP3094583B2 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2015196753A (en) * 2014-03-31 2015-11-09 積水化学工業株式会社 polyvinyl acetal resin

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2015196753A (en) * 2014-03-31 2015-11-09 積水化学工業株式会社 polyvinyl acetal resin

Also Published As

Publication number Publication date
JP3094583B2 (en) 2000-10-03

Similar Documents

Publication Publication Date Title
US4018826A (en) Process for preparing polyvinylamine and salts thereof
JPH04283537A (en) Process for producing alkoxyalkanoic acid or salt thereof
US3920760A (en) Process for the production of neopentyl glycol
USRE30362E (en) Process for preparing polyvinylamine and salts thereof
US2475996A (en) Dinitro alcohols and process of producing the same from unsaturated aldehydes
JPH05140217A (en) Purification of polyvinylaromatic acetal
JP2680394B2 (en) Oligomers of phenothiazine and formaldehyde and their preparation and their use in reactor scale prevention
CN112739675B (en) Method for recovering high quality 3-methyl-but-3-en-1-ol
CN108912002A (en) The preparation method of aminomethylbenzoic acid
JPH02222731A (en) Recovery method of catalyser
JPS5819605B2 (en) Purification of crude chlorophosphazene compounds by water treatment
TW575579B (en) Process for the recovery of N-phosphonomethylglycine
US4275002A (en) Process for preparing polymeric colorants having a poly(vinylamine) backbone
JPH08157401A (en) Production of trimethylolpropane and ditrimethylolpropane
JPS60105664A (en) Production of 4-methylimidazole
JP6977357B2 (en) Thiophene sulfonate
US4021495A (en) Purification of β-naphthol
RU2291739C2 (en) Method of the recuperation of the ethers of cellulose from the water solutions by the ultrafiltration with the improved shift effect
JP2000344696A (en) Production of adamantanediol
JPH09169683A (en) Purification of polyoxyalkylene derivative
JP2946944B2 (en) Method for producing alkylaminophenols
JP3207954B2 (en) Method for producing 2-acetylpyrazine
US4136088A (en) Method for recovering low molecular weight polymers
US4418226A (en) Process for refining waste liquor
KR101006003B1 (en) Method of manufacturing polyoxy alkylene alkenyl ether using two-phase reaction

Legal Events

Date Code Title Description
FPAY Renewal fee payment (prs date is renewal date of database)

Year of fee payment: 7

Free format text: PAYMENT UNTIL: 20070804

FPAY Renewal fee payment (prs date is renewal date of database)

Free format text: PAYMENT UNTIL: 20080804

Year of fee payment: 8

FPAY Renewal fee payment (prs date is renewal date of database)

Year of fee payment: 9

Free format text: PAYMENT UNTIL: 20090804

FPAY Renewal fee payment (prs date is renewal date of database)

Year of fee payment: 10

Free format text: PAYMENT UNTIL: 20100804

LAPS Cancellation because of no payment of annual fees