JPS61200105A - Method for dissolving polyvinyl ketal in water - Google Patents

Method for dissolving polyvinyl ketal in water

Info

Publication number
JPS61200105A
JPS61200105A JP4158285A JP4158285A JPS61200105A JP S61200105 A JPS61200105 A JP S61200105A JP 4158285 A JP4158285 A JP 4158285A JP 4158285 A JP4158285 A JP 4158285A JP S61200105 A JPS61200105 A JP S61200105A
Authority
JP
Japan
Prior art keywords
water
ketal
polyvinyl
ketalization
degree
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.)
Pending
Application number
JP4158285A
Other languages
Japanese (ja)
Inventor
Hisafumi Nakamura
中村 尚史
Ichiro Sakurada
桜田 一郎
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.)
KAKUYOKAI
Original Assignee
KAKUYOKAI
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 KAKUYOKAI filed Critical KAKUYOKAI
Priority to JP4158285A priority Critical patent/JPS61200105A/en
Publication of JPS61200105A publication Critical patent/JPS61200105A/en
Pending legal-status Critical Current

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  • Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
  • Processes Of Treating Macromolecular Substances (AREA)

Abstract

PURPOSE:To enable the dissolution of a polyvinyl ketal in water without causing the deketalization, by dissolving a polyvinyl ketal having a specific ketalization degree in neutral or alkaline water at a low temperature. CONSTITUTION:A polyvinyl ketal having a ketalization degree of 8-60(mol)% is dissolved in neutral or alkaline water at <30 deg.C. A resin having a ketalization degree of 8-25% is dissolved at <30 deg.C, and the one having the ketalization degree of 15-60% is dissolved at 0 deg.C. EFFECT:The dissolution of polyvinyl ketal is caused by the formation of an ice-like structure by the hydrophobic ketal group introduced into polyvinyl alcohol and water and when the temperature is increased, the ice-like structure is destructed to cause the aggregation of the molecules and the clouding of the solution. When the ketalization degree of the polymer is high, the amount of hydration is decreased by the decrease in the hydrophilic OH group, and accordingly, slight destruction of the ice-like structure causes the clouding of the solution and the polymer is insoluble in water at a high temperature.

Description

【発明の詳細な説明】 (産業上の利用分野) この発明はポリビニルケタールの水溶解方法に関するも
のである。
DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) This invention relates to a method for dissolving polyvinyl ketal in water.

(従来の技術) 熱可塑性合成樹脂は、フィルム、その他の成形品に加工
されて包装材料、その他の材料として広く利用されてい
るが、水に不溶性である。近年、水可溶性の合成樹脂が
要望されている。例えば、病人の汚れた衣料を水溶性フ
ィルムに包装したまま洗濯し、洗濯中にフィルムが溶け
てなくなれば衛生上、取扱上有利である。また特定の目
的のために身体内で使用される成形品が、ある期間後に
体内で溶失されることは好ましいことである。また経口
薬を充填したカプセルが、ある条件下で徐々に溶解し、
薬が徐々に浸出してくるようなものが要望されている。
(Prior Art) Thermoplastic synthetic resins are processed into films and other molded products and are widely used as packaging materials and other materials, but they are insoluble in water. In recent years, there has been a demand for water-soluble synthetic resins. For example, if a sick person's soiled clothing is washed while still wrapped in a water-soluble film, and the film melts away during washing, it is advantageous in terms of hygiene and handling. It is also advantageous for molded articles used within the body for specific purposes to be dissolved within the body after a certain period of time. Also, capsules filled with oral drugs gradually dissolve under certain conditions.
There is a demand for something that allows the drug to gradually leach out.

従来、水可溶性合成樹脂としてポリビニルアルコールが
知られているが、加熱乾燥されたポリビニルアルコール
を水に溶解するには水の沸点付近まで加熱しなけれずな
らず常温の水では不溶性である。一方ポリビニルアルコ
ールにケトン類を反応させて得られるポリビニルケター
ルは1機械的物性が優れフィルムその他の成形品に成形
できる合成樹脂であるが、ポリビニルアルコールのケタ
ール化反応が、ポリビニルアルコールのアセタール化反
応に比べて容易でなかったため、その性能の解析も十分
に行なわれず汎用樹脂として余り知られていなかった。
Conventionally, polyvinyl alcohol has been known as a water-soluble synthetic resin, but in order to dissolve heat-dried polyvinyl alcohol in water, it must be heated to around the boiling point of water, and it is insoluble in water at room temperature. On the other hand, polyvinyl ketal obtained by reacting polyvinyl alcohol with ketones is a synthetic resin that has excellent mechanical properties and can be molded into films and other molded products, but the ketalization reaction of polyvinyl alcohol is similar to the acetalization reaction of polyvinyl alcohol. Because it was not easy to compare, its performance was not sufficiently analyzed and it was not well known as a general-purpose resin.

本発明者らは低温で水溶性の熱可塑性合成樹脂としてポ
リビニルケタールに着1」L、、ケタール化度5モル%
以上のポリビニルケタールは酸性水溶液中では下式のよ
うに脱ケタール化され、脱ケタール化されたポリビニル
アルコールは分子配列が乱れているため水溶性となるこ
とを見いだしたのである(特願昭58−.144164
号参照)。
The present inventors applied polyvinyl ketal as a thermoplastic synthetic resin that is water-soluble at low temperatures.
It was discovered that the polyvinyl ketal mentioned above is deketalized in an acidic aqueous solution as shown in the following formula, and that the deketalized polyvinyl alcohol becomes water-soluble because its molecular arrangement is disordered (Patent Application No. 1983- .144164
(see issue).

−CH,−CH−CI(、−CH− →   −CH,−CH−CH,−CH−+    >
C=01    1    R′ CHOH しかしながら上記の水溶解法は、ポリビニルケタールが
脱ケタール化されたポリビニルアルコールが水溶性とな
るものである。本発明者らはさらに研究を続け、ケター
ル化度5〜25モル%のポリビニルケタールを温度30
〜45℃の中性またはアルカリ性の水で、ポリビニルケ
タールが脱ケタール化することなく溶解する方法を発明
した(特願昭59−29162号参照)。
-CH, -CH-CI(, -CH- → -CH, -CH-CH, -CH-+ >
C=01 1 R' CHOH However, in the above-mentioned water dissolution method, polyvinyl alcohol from which polyvinyl ketal has been deketalized becomes water-soluble. The present inventors continued their research and produced polyvinyl ketal with a degree of ketalization of 5 to 25 mol% at a temperature of 30%.
We have invented a method for dissolving polyvinyl ketal in neutral or alkaline water at ~45°C without deketalization (see Japanese Patent Application No. 59-29162).

(発明が解決しようとする問題点) 上記のポリビニルケタールを脱ケタール化することなく
水で溶解する方法は、温度が比較的に高いので、さらに
温度を低くした場合について引続き研究し、温度が低い
ほどケタール化度の範囲が広まることを見出だしたので
ある。
(Problem to be solved by the invention) Since the above method of dissolving polyvinyl ketal in water without deketalizing it requires a relatively high temperature, we will continue to study the case of lowering the temperature. They found that the range of the degree of ketalization widens as the temperature increases.

(問題点を解決するための手段) ケタール化度8〜60モル%のポリビニルケタールを温
度30℃未満の中性またはアルカリ性の水で溶解するこ
とを特徴とするポリビニルケタールの水溶解方法である
(Means for Solving the Problems) A method for dissolving polyvinyl ketal in water is characterized in that polyvinyl ketal having a degree of ketalization of 8 to 60 mol % is dissolved in neutral or alkaline water at a temperature of less than 30°C.

ポリビニルケタールの製造法として、ケトンをアルキル
ケタールに変化させてポリビニルアルコールと反応させ
る方法(西ドイツ特許第679792号公報参照)が知
られているが、本発明者らは、ポリビニルアルコールに
ケトンを直接に反応させてポリビニルケタールを製造す
る方法を発明し、先に特許出願した(特願昭58−14
41.63号参照)。
As a method for producing polyvinyl ketal, a method of converting a ketone into an alkyl ketal and reacting it with polyvinyl alcohol is known (see West German Patent No. 679,792). He invented a method for producing polyvinyl ketal by reacting it, and filed a patent application earlier (Japanese Patent Application No. 58-14).
41.63).

ポリビニルアルコールに反応させルケトン類としては、
アセトン、メチルエチルケ1−ン、ジエチルケトン、メ
チルプロピルケトン、エチルプロピルケトン、アセトフ
ェノン、メチルシクロへキシルケトン、シクロヘキサノ
ンなどが例示される。
As ketones reacted with polyvinyl alcohol,
Examples include acetone, methylethylketone, diethylketone, methylpropylketone, ethylpropylketone, acetophenone, methylcyclohexylketone, and cyclohexanone.

この発明に使用されるポリビニルケタールは、上記の製
造法に制限されず、いかなる方法で製造されたものでも
よい。
The polyvinyl ketal used in this invention is not limited to the above-mentioned production method, and may be produced by any method.

この発明に使用されるポリビニルケタールのケタール化
度は8〜60モル%の範囲であり、このポリビニルケタ
ールが中性またはアルカリ性の水に溶ける温度は30℃
未満である。ポリビニルケタールの水溶性は、ケタール
化度の範囲と温度の範囲とに関係し、上限の温度30℃
未満の場合はケタール化度の範囲は8〜25未満モル%
であり、温度O′Cの場合は15〜60モル%であり、
上記ケタール化度の下限および上限は温度の変化に応じ
てほぼ直線的に変化する。上記の水の温度とケタール化
度との関係は図面のグラフに示すとおりであり、このグ
ラフは水多くの実験により得たものである。
The degree of ketalization of the polyvinyl ketal used in this invention is in the range of 8 to 60 mol%, and the temperature at which this polyvinyl ketal dissolves in neutral or alkaline water is 30°C.
less than The water solubility of polyvinyl ketal is related to the range of degree of ketalization and the range of temperature, with an upper limit temperature of 30°C.
If the degree of ketalization is less than 8 to less than 25 mol%
and at a temperature of O'C, it is 15 to 60 mol%,
The lower and upper limits of the degree of ketalization change approximately linearly with changes in temperature. The relationship between the temperature of water and the degree of ketalization is as shown in the graph in the drawing, which was obtained through numerous experiments.

(発明の作用) ポリビニルケタールが水に溶解するのは、ポリビニルア
ルコール中に導入された疎水性のケタール基が水と水様
構造を形成するためであり、温度が上昇すると上記水様
構造が破壊されて分子同士が凝集して白濁し、またケタ
ール化度が高い場合は分子全体を溶解状態に保ってきた
親水性の水酸基の減少によって水和量が減少しているの
で、僅かに上記水様構造が破壊されても白濁してくるた
め、高温の水に溶解しなくなるものと考えられる。
(Action of the invention) Polyvinyl ketal dissolves in water because the hydrophobic ketal group introduced into polyvinyl alcohol forms an aqueous structure with water, and when the temperature rises, the aqueous structure breaks down. When the degree of ketalization is high, the amount of hydration decreases due to a decrease in the hydrophilic hydroxyl groups that keep the entire molecule in a dissolved state. It is thought that even if the structure is destroyed, it becomes cloudy and becomes insoluble in high-temperature water.

(実施例) 実施例1 ポリビニルアルコール(重合度1800) 5.0gを
ジメチルスルホキシド100m1に溶解したのちパラト
ルエンスルホン酸0.5gを加えて溶解させた。このポ
リビニルアルコール溶液にアセトン25.0m1(ポリ
ビニルアルコールの2基本モルに対して6.0モルに相
当)を加え、40℃の恒I!!槽中で20時間かくはん
して反応させた。反応終了後、IN−苛性ソーダ水溶液
を加えて完全に中和した。この反応物を酢酸エチルで沈
でんさせたのち減圧乾燥し、この乾燥物を80%メタノ
ールで溶解し酢酸エチルで沈でんさせた沈でん物を減圧
乾燥させる操作を2回繰り返して精製し、ケタール化度
49.4モル%のポリビニルケタール5.5gを得た。
(Example) Example 1 After dissolving 5.0 g of polyvinyl alcohol (degree of polymerization 1800) in 100 ml of dimethyl sulfoxide, 0.5 g of para-toluenesulfonic acid was added and dissolved. 25.0 ml of acetone (equivalent to 6.0 mol per 2 basic moles of polyvinyl alcohol) was added to this polyvinyl alcohol solution, and the solution was heated to a constant temperature of 40°C. ! The reaction mixture was stirred in a tank for 20 hours. After the reaction was completed, IN-caustic soda aqueous solution was added to completely neutralize. This reaction product was precipitated with ethyl acetate and then dried under reduced pressure. The dried product was dissolved in 80% methanol, precipitated with ethyl acetate, and the precipitate was dried under reduced pressure. This procedure was repeated twice to purify the product, and the degree of ketalization was 49. 5.5 g of polyvinyl ketal of .4 mol % was obtained.

このポリビニルケタールを80%エチルアルコールに溶
解し、この溶液から厚さ0.04nnのポリビニルケタ
ールフィルムを成形した。次いでこのポリビニルケター
ルフィルムを0℃のpH6,5の蒸溜水中、および円+
12のアルカリ性水溶液中で処理したところ、前者は5
0分間、後者は60分間で完全に溶解した。上記2個の
ポリビニルケタール水溶液中のアセトンをヨードホルム
法で定量したところ、アセ1〜ンは全く検出されず、溶
解ポリビニルケタールは全く説ケタール化されていなか
った。
This polyvinyl ketal was dissolved in 80% ethyl alcohol, and a polyvinyl ketal film with a thickness of 0.04 nn was molded from this solution. This polyvinyl ketal film was then placed in distilled water at 0°C and pH 6.5.
When treated in an alkaline aqueous solution of 12, the former was 5
0 min, the latter completely dissolved in 60 min. When the acetone in the aqueous solutions of the above two polyvinyl ketals was quantified by the iodoform method, no acetone was detected, and the dissolved polyvinyl ketals were not converted into ketals at all.

更に上記のポリビニルケタール水溶液に1/ION −
塩酸水溶液10ccを加えて1時間放置して脱ケタール
化を行なわせたのちアセトンを定量したところ49.4
モル%であって、上記水およびアルカリ性の水ではポリ
ビニルケタールは加水分解されることなく水に溶解する
ことが分った。このポリビニルケタール水溶液の温度を
次第に上昇すると8℃において白濁した。
Furthermore, 1/ION − is added to the above polyvinyl ketal aqueous solution.
After adding 10 cc of hydrochloric acid aqueous solution and allowing it to stand for 1 hour to perform deketalization, the amount of acetone was determined to be 49.4.
It was found that in the above water and alkaline water, polyvinyl ketal was dissolved in water without being hydrolyzed. When the temperature of this aqueous polyvinyl ketal solution was gradually increased, it became cloudy at 8°C.

実施例2 実施例1と同じポリビニルアルコール溶液にアセトン1
2.5ml (ポリビニルアルコールの2基本モルに対
して3.0モルに相当)を加えた以外は実施例1と同様
に操作してケタール化度42゜0モル%のポリビニルケ
・タール5.12gを得、次いで実施例1と同様にして
ポリビニルケタールフィルムを成形した。このポリビニ
ルケタールフィルムをlOoCのPH6,5の蒸溜水中
、およびPH2のアルカリ性水溶液中で処理したところ
、前者は85分間、後者は100分間で完全に溶解した
。実施例1と同様にポリビニルケタール水溶液からはア
セトンは全く検出されず、ポリビニルケタールは脱ケタ
ール化されることなく水に溶解している。このポリビニ
ルケタール水溶液は14℃に昇温すると白濁した。
Example 2 Add 1 part of acetone to the same polyvinyl alcohol solution as in Example 1.
5.12 g of polyvinyl ketal with a degree of ketalization of 42.0 mol % was prepared in the same manner as in Example 1 except that 2.5 ml (equivalent to 3.0 mol per 2 basic mol of polyvinyl alcohol) was added. A polyvinyl ketal film was then molded in the same manner as in Example 1. When this polyvinyl ketal film was treated in distilled water with a pH of 6.5 at lOoC and an alkaline aqueous solution with a pH of 2, the former was completely dissolved in 85 minutes and the latter in 100 minutes. As in Example 1, no acetone was detected in the polyvinyl ketal aqueous solution, and the polyvinyl ketal was dissolved in water without being deketalized. This polyvinyl ketal aqueous solution became cloudy when heated to 14°C.

実施例3 実施例1と同じポリビニルアルコール溶液にアセトン5
.0m1(ポリビニルアルコールの2基本モルに対して
1.2モルに相当)を加えた以外は実施例1と同様に操
作してケタール化度29,4モル%にポリビニルケター
ル5.31gを得、次いで実施例1と同様にしてポリビ
ニルケタールフィルムを成形し、このフィルムを20℃
の円16.5の蒸溜水中、およびP!112のアルカリ
性水溶液中で処理したところ、前者は140分間、後者
は200分間で完全に溶解した。実施例1と同様にポリ
ビニルケタール水溶液からアセトンは全く検出されず、
ポリビニルケタールは加水分解されることなく水に溶解
している。このポリビニルケタール水溶液は25℃に昇
温すると白濁した。
Example 3 Acetone 5 was added to the same polyvinyl alcohol solution as in Example 1.
.. 5.31 g of polyvinyl ketal was obtained with a degree of ketalization of 29.4 mol % by the same procedure as in Example 1 except that 0 ml (corresponding to 1.2 mol per 2 basic mol of polyvinyl alcohol) was added. A polyvinyl ketal film was formed in the same manner as in Example 1, and the film was heated at 20°C.
of circle 16.5 in distilled water, and P! When treated in an alkaline aqueous solution of No. 112, the former was completely dissolved in 140 minutes and the latter was completely dissolved in 200 minutes. As in Example 1, no acetone was detected from the polyvinyl ketal aqueous solution,
Polyvinyl ketal is dissolved in water without being hydrolyzed. This polyvinyl ketal aqueous solution became cloudy when heated to 25°C.

実施例4 実施例1と同じポリビニルアルコール溶液にアセトン2
.09m1 (ポリビニルアルコールの2基本モルに対
して0.50モルに相当)を加えた以外は実施例1と同
様に操作してケタール化度19.6モル%のポリビニル
ケタール5.04gを得、次いで実施例1と同様にして
ポリビニルケタールフィルムを成形し、このフィルムを
0℃のPl+ 6.5の蒸溜水中、およびPI(12の
アルカリ性の水中で処理したところ、前者は180分間
、後者は200分間で完全に溶解した。実施例1と同様
にポリビニルケタール水溶液からアセトンは全く検出さ
れず、ポリビニルケタールは加水分解されることなく水
に溶解している。このポリビニルケタール水溶液は30
℃に昇温するも白濁することがなく、また加水分解もさ
れていなかった。
Example 4 Acetone 2 was added to the same polyvinyl alcohol solution as in Example 1.
.. 09m1 (equivalent to 0.50 mol per 2 basic moles of polyvinyl alcohol) was operated in the same manner as in Example 1 to obtain 5.04 g of polyvinyl ketal with a degree of ketalization of 19.6 mol%, and then A polyvinyl ketal film was formed in the same manner as in Example 1, and this film was treated in distilled water of PI + 6.5 and alkaline water of PI (12) at 0°C, the former for 180 minutes and the latter for 200 minutes. As in Example 1, no acetone was detected in the polyvinyl ketal aqueous solution, and the polyvinyl ketal was dissolved in water without being hydrolyzed.
Even when the temperature was raised to ℃, it did not become cloudy and was not hydrolyzed.

実施例5 実施例1と同じポリビニルアルコール溶液にメチルエチ
ルケトン2.02m1 (ポリビニルアルコールの2基
本モルに対して0.40モルに相当)を加えた以外は実
施例1と同様に操作してケタール化度13.6モル%の
ポリビニルケタール5.30gを得、次いでポリビニル
ケタールフィルムを0℃のPH6,5の蒸溜水中、およ
びpH12のアルカリ性水溶液中で処理したところ、前
者は500分間、後者は600分間で完性に溶解した。
Example 5 The degree of ketalization was determined in the same manner as in Example 1, except that 2.02 ml of methyl ethyl ketone (equivalent to 0.40 mol per 2 basic moles of polyvinyl alcohol) was added to the same polyvinyl alcohol solution as in Example 1. 5.30 g of polyvinyl ketal with a concentration of 13.6 mol% was obtained, and then the polyvinyl ketal film was treated in distilled water with a pH of 6.5 at 0°C and an alkaline aqueous solution with a pH of 12. Completely dissolved.

実施例1と同様にポリビニルケタール水溶液からはメチ
ルエチルケトンは全く検出されず、ポリビニルケタール
は加水分解することなく水に溶解している。このポリビ
ニルケタール水溶液は30℃に昇温するも白濁すること
がなく、また加水分解もさ才していなかった。
As in Example 1, no methyl ethyl ketone was detected in the polyvinyl ketal aqueous solution, and the polyvinyl ketal was dissolved in water without being hydrolyzed. This polyvinyl ketal aqueous solution did not become cloudy even when the temperature was raised to 30° C., and hydrolysis did not occur.

(発明の効果) 従来水不溶性と考えられていたポリビニルケタールを3
0℃未満の温度で、しかも広い範囲のケタール化度のポ
リビニルケタールを加水分解することなく溶解すること
ができる。
(Effect of the invention) Polyvinyl ketal, which was conventionally thought to be water-insoluble, was
At temperatures below 0° C., polyvinyl ketals with a wide range of degrees of ketalization can be dissolved without hydrolysis.

【図面の簡単な説明】[Brief explanation of the drawing]

図面はポリビニルケタールのケタール化度と水溶解温度
との範囲を示すグラフである。 特許出願人 財団法人 覚 誉 会 代理人 弁理士 坂 野 威 夫 l!    吉  1) 了  司 ケタール化!(引しclo) 手続補正帯 昭和60年4月40 1、事件の表示 昭和60年特許願第 41582    号2、発明の
名称 ポリビニルケタールの水溶W? 方法 3゜補正をするに 事件との関係  特許出願人 居  所  京都市中京区室町通二条南入蛸薬師町27
3番地名 称  財叩法人 覚誉会 7、補正の内容 (1)明に@男、第6頁5行目 「水と水様構造」を「水の水様構造」に訂正。 (2)明細書第9頁4〜.5行目 r29.4モル%にポリビニルケタール」全r29.4
モル%のポリビニルケタール」に訂正。
The drawing is a graph showing the range of the degree of ketalization of polyvinyl ketal and the water dissolution temperature. Patent applicant: Kakuhokai Foundation, agent: Takeo Sakano, patent attorney! Yoshi 1) Ryo Tsukasa turned into a ketal! (Reference clo) Procedural amendment April 40, 1985 1. Indication of the case Patent application No. 41582 of 1985 2. Name of the invention Water-soluble polyvinyl ketal W? Method 3: Relationship to the case when making an amendment Patent applicant's residence 27, Muromachi-dori 2-jo Minamiiri Takoyakushi-cho, Nakagyo-ku, Kyoto City
Address 3 Name Zaibaku Corporation Kakuyokai 7 Contents of amendment (1) Akira @man, page 6, line 5, "water and water-like structure" is corrected to "water-like structure of water." (2) Specification, page 9, 4-. Polyvinyl ketal in 5th line r29.4 mol% Total r29.4
Corrected to "mol% polyvinyl ketal".

Claims (1)

【特許請求の範囲】 〔1〕ケタール化度8〜60モル%のポリビニルケター
ルを温度30℃未満の中性またはアルカリ性の水で溶解
することを特徴とするポリビニルケタールの水溶解方法
。 〔2〕温度30度未満ではケタール化度8〜25未満モ
ル%、0℃ではケタール化度15〜60モル%で溶解す
る特許請求の範囲第1項に記載のポリビニルケタールの
本溶解方法。
[Scope of Claims] [1] A method for dissolving polyvinyl ketal in water, which comprises dissolving polyvinyl ketal having a degree of ketalization of 8 to 60 mol% in neutral or alkaline water at a temperature of less than 30°C. [2] The present method for dissolving polyvinyl ketal according to claim 1, wherein the polyvinyl ketal is dissolved at a degree of ketalization of 8 to less than 25 mol% at a temperature of less than 30 degrees Celsius, and at a degree of ketalization of 15 to 60 mol% at 0 degrees Celsius.
JP4158285A 1985-03-01 1985-03-01 Method for dissolving polyvinyl ketal in water Pending JPS61200105A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP4158285A JPS61200105A (en) 1985-03-01 1985-03-01 Method for dissolving polyvinyl ketal in water

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP4158285A JPS61200105A (en) 1985-03-01 1985-03-01 Method for dissolving polyvinyl ketal in water

Publications (1)

Publication Number Publication Date
JPS61200105A true JPS61200105A (en) 1986-09-04

Family

ID=12612429

Family Applications (1)

Application Number Title Priority Date Filing Date
JP4158285A Pending JPS61200105A (en) 1985-03-01 1985-03-01 Method for dissolving polyvinyl ketal in water

Country Status (1)

Country Link
JP (1) JPS61200105A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2001066082A3 (en) * 2000-03-10 2002-01-24 Greither Peter Shaped body comprising a shaped body shell and a shaped body content, especially capsules with a one-piece capsule shell, and method for producing shaped bodies and protective coats

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0346008A (en) * 1989-07-14 1991-02-27 Csk Corp Robot control system

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0346008A (en) * 1989-07-14 1991-02-27 Csk Corp Robot control system

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2001066082A3 (en) * 2000-03-10 2002-01-24 Greither Peter Shaped body comprising a shaped body shell and a shaped body content, especially capsules with a one-piece capsule shell, and method for producing shaped bodies and protective coats

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