TW202106724A - Polyvinyl alcohol, method for producing same and use of same - Google Patents
Polyvinyl alcohol, method for producing same and use of same Download PDFInfo
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- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
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- C08F114/00—Homopolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by a halogen
- C08F114/02—Monomers containing chlorine
- C08F114/04—Monomers containing two carbon atoms
- C08F114/06—Vinyl chloride
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- C08J2329/00—Characterised by the use of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an alcohol, ether, aldehydo, ketonic, acetal, or ketal radical; Hydrolysed polymers of esters of unsaturated alcohols with saturated carboxylic acids; Derivatives of such polymer
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Abstract
Description
本發明係關於一種聚乙烯醇,其皂化度及黏度平均聚合度在特定的範圍,進一步於末端含有特定量的醛基,且具有特定的吸光度。又,本發明係關於使用了該聚乙烯醇的交聯物、乙烯基化合物之懸浮聚合用分散穩定劑、及乙烯系樹脂之製造方法。The present invention relates to a polyvinyl alcohol whose saponification degree and viscosity average degree of polymerization are in a specific range, further contains a specific amount of aldehyde groups at the end, and has a specific absorbance. Moreover, this invention relates to the manufacturing method of the dispersion stabilizer for suspension polymerization using this crosslinked product of polyvinyl alcohol, a vinyl compound, and a vinyl resin.
具有反應活性的官能基之聚乙烯醇(以下有時將聚乙烯醇簡略記載為「PVA」),係自以往被使用於接著劑、紙塗布劑、偏光薄膜、乙烯基化合物(例如氯乙烯)之懸浮聚合用分散穩定劑等各種製品。尤其反應活性部位與交聯劑之交聯反應所合成之交聯高分子由於分子鏈之活動被拘束於三次元方向,因此通常強度、耐熱性、耐溶劑性比同種的線狀高分子更優異,尤其耐水性優異,故其有用性高。又,作為PVA之廣泛用途,而有乙烯基化合物之懸浮聚合用分散穩定劑,使用各種PVA。Polyvinyl alcohol with reactive functional groups (hereinafter sometimes abbreviated as "PVA"), is used in adhesives, paper coating agents, polarizing films, vinyl compounds (such as vinyl chloride) Various products such as dispersion stabilizer for suspension polymerization. In particular, the cross-linked polymer synthesized by the cross-linking reaction of the reactive site and the cross-linking agent is constrained in the three-dimensional direction due to the movement of the molecular chain, so generally the strength, heat resistance, and solvent resistance are better than the same kind of linear polymer. , Especially excellent water resistance, so its usefulness is high. In addition, various PVAs are used as dispersion stabilizers for suspension polymerization of vinyl compounds as a wide range of uses of PVA.
尤其作為交聯性能高的具有反應活性的官能基之改性PVA,可列舉:具有乙醯乙醯基所代表之被2個羰基挾住之亞甲基氫的結構之改性PVA(專利文獻1)。In particular, as a modified PVA with high crosslinking properties and reactive functional groups, there can be cited: modified PVA with a structure of methylene hydrogen held by two carbonyl groups represented by an acetyl acetyl group (Patent Document 1).
又,在專利文獻2及3中,基於使乙烯基化合物之聚合時的聚合穩定性提升而抑制所得之乙烯系聚合物的粗粒化之目的,將經熱處理之PVA使用於乙烯基化合物之懸浮聚合用分散穩定劑。此外,在本說明書中聚合穩定性係意指:由於在聚合時包含乙烯基化合物之液滴的分散性良好,因此以結果而言,可得到粗粒化被抑制且直徑一致的乙烯系聚合物之粒子。 [先前技術文獻] [專利文獻]In addition, in Patent Documents 2 and 3, for the purpose of improving the polymerization stability during the polymerization of the vinyl compound and suppressing the coarsening of the obtained vinyl polymer, the heat-treated PVA is used for the suspension of the vinyl compound Dispersion stabilizer for polymerization. In addition, the polymerization stability in this specification means that since the dispersion of the vinyl compound-containing droplets during polymerization is good, as a result, a vinyl polymer with a uniform diameter and suppressed coarsening can be obtained. Of particles. [Prior Technical Literature] [Patent Literature]
[專利文獻1]日本特開2014-205826號公報 [專利文獻2]日本特開昭51-45189號公報 [專利文獻3]日本特開2004-250695號公報[Patent Document 1] JP 2014-205826 A [Patent Document 2] Japanese Patent Application Laid-Open No. 51-45189 [Patent Document 3] JP 2004-250695 A
[發明欲解決之課題][The problem to be solved by the invention]
然而,在專利文獻1中使用之倍羰烯係對於生物之毒性高,若有空氣與蒸氣混合則有爆炸之危險性,而追求開發更安全地合成具有反應活性的官能基之改性PVA之手法。又,在專利文獻1中有必要使用特殊的交聯劑,難以使用酸等而簡便地得到耐水性優異的交聯物。However, the foldcarboxene system used in Patent Document 1 is highly toxic to organisms, and there is a danger of explosion if air and steam are mixed, and it is pursued to develop a safer synthesis of modified PVA with reactive functional groups. Technique. In addition, in Patent Document 1, it is necessary to use a special crosslinking agent, and it is difficult to use an acid or the like to easily obtain a crosslinked product having excellent water resistance.
又,當使用專利文獻2或3所記載之改性PVA作為懸浮聚合用分散穩定劑時,雖然於乙烯基化合物聚合時的聚合穩定性可見到有改善,但於所得之乙烯系聚合物多微粉等,對於近年追求之要求而言並不充分。再者,殘留因將乙烯系聚合物作成薄片狀時的異物、缺陷所致之魚眼多等課題。In addition, when the modified PVA described in Patent Document 2 or 3 is used as a dispersion stabilizer for suspension polymerization, although the polymerization stability during the polymerization of the vinyl compound is improved, the resultant vinyl polymer is more finely powdered. And so on, it is not sufficient for the requirements pursued in recent years. Furthermore, problems such as many fisheyes caused by foreign matter and defects when the ethylene-based polymer is made into a sheet form remain.
本發明係為了解決上述課題而進行者,其目的為提供一種PVA,其係在使用作為乙烯基化合物之懸浮聚合用分散穩定劑時,可在所得之乙烯系樹脂中抑制粗大粒子之形成的同時,可得到直徑一致的粒子,而且可抑制魚眼之產生。又,其目的為提供一種可簡便地得到耐水性優異的交聯物之PVA。 [用以解決課題之手段]The present invention was made in order to solve the above-mentioned problems, and its purpose is to provide a PVA which, when used as a dispersion stabilizer for suspension polymerization of a vinyl compound, can suppress the formation of coarse particles in the resulting vinyl resin. , Can obtain particles with the same diameter, and can suppress the production of fish eyes. In addition, its purpose is to provide a PVA that can easily obtain a cross-linked product excellent in water resistance. [Means to solve the problem]
本發明係發現一種解決上述課題之PVA,而完成本發明,其係皂化度及黏度平均聚合度在特定的範圍,進一步於末端含有特定量的醛基,且具有特定的吸光度之PVA。The present invention is to find a PVA to solve the above-mentioned problems, and complete the present invention. The saponification degree and viscosity average degree of polymerization are in a specific range, and further contains a specific amount of aldehyde groups at the end and has a specific absorbance.
亦即,上述課題可藉由提供一種聚乙烯醇而解決,其係皂化度為70莫耳%以上小於99.9莫耳%,黏度平均聚合度為400以上小於1800,於末端含有0.05莫耳%以上小於0.5莫耳%的醛基,且0.1質量%水溶液之280nm的吸光度為0.17以上小於0.55之聚乙烯醇。That is, the above-mentioned problem can be solved by providing a polyvinyl alcohol with a saponification degree of 70 mol% or more and less than 99.9 mol%, a viscosity average polymerization degree of 400 or more and less than 1800, and 0.05 mol% or more at the end. Polyvinyl alcohol with an aldehyde group of less than 0.5 mol% and an absorbance of 0.17 or more and less than 0.55 at 280 nm of a 0.1% by mass aqueous solution.
此時,於末端具有下述式(1)所表示之結構為較佳。In this case, it is preferable to have a structure represented by the following formula (1) at the terminal.
(式(1)中,X表示單鍵、可具有取代基之伸烷基或可具有取代基之伸芳基,*表示鍵結鍵)。 (In formula (1), X represents a single bond, an alkylene group which may have a substituent or an arylene group which may have a substituent, and * represents a bonding bond).
又,X為碳數1~6之伸烷基亦為較佳。Furthermore, it is also preferable that X is an alkylene group having 1 to 6 carbon atoms.
此時,上述聚乙烯醇之理想的製造方法為在二醛或三醛之存在下使乙烯酯聚合而得到聚乙烯酯後,將該聚乙烯酯皂化。In this case, the ideal production method of the above-mentioned polyvinyl alcohol is to polymerize vinyl ester in the presence of dialdehyde or trialdehyde to obtain polyvinyl ester, and then saponify the polyvinyl ester.
又,本發明之理想的實施態樣為含有上述聚乙烯醇之乙烯基化合物之懸浮聚合用分散穩定劑。在上述聚乙烯醇之存在下將乙烯基化合物懸浮聚合之乙烯系樹脂之製造方法亦為本發明之理想的實施態樣。In addition, an ideal embodiment of the present invention is a dispersion stabilizer for suspension polymerization containing the above-mentioned vinyl compound of polyvinyl alcohol. The method for producing vinyl resin by suspension polymerization of vinyl compound in the presence of the above polyvinyl alcohol is also an ideal embodiment of the present invention.
再者,本發明之理想的實施態樣為一種交聯物,係上述聚乙烯醇經交聯的交聯物,其係將包含前述交聯物之厚度100μm的薄膜浸漬於80℃之熱水1小時之際的溶出率小於10%。此時,上述交聯物之理想的製造方法為在酸觸媒之存在下將前述聚乙烯醇交聯。 [發明之效果]Furthermore, an ideal embodiment of the present invention is a cross-linked product, which is a cross-linked product of the above-mentioned polyvinyl alcohol, in which a film with a thickness of 100 μm containing the aforementioned cross-linked product is immersed in hot water at 80°C. The dissolution rate in 1 hour is less than 10%. At this time, an ideal method for producing the above-mentioned cross-linked product is to cross-link the above-mentioned polyvinyl alcohol in the presence of an acid catalyst. [Effects of Invention]
若使用本發明之PVA作為乙烯基化合物之懸浮聚合用分散穩定劑,則藉由顯示高聚合穩定性,而可在所得之乙烯系樹脂中抑制粗大粒子之形成的同時,可得到直徑一致的粒子,而且可抑制魚眼之產生。又,可藉由使用本發明之PVA,而簡便地得到耐水性優異的交聯物。If the PVA of the present invention is used as a dispersion stabilizer for suspension polymerization of vinyl compounds, by exhibiting high polymerization stability, the formation of coarse particles in the resulting vinyl resin can be suppressed, and particles with uniform diameters can be obtained. , And can inhibit the production of fish eyes. In addition, by using the PVA of the present invention, a cross-linked product excellent in water resistance can be easily obtained.
[用以實施發明的形態][Form to implement the invention]
[聚乙烯醇] 本發明之聚乙烯醇之特徵為:皂化度為70莫耳%以上小於99.9莫耳%,黏度平均聚合度為400以上小於1800,於末端含有0.05莫耳%以上小於0.5莫耳%的醛基,且0.1質量%水溶液之280nm的吸光度為0.17以上小於0.55。[Polyvinyl Alcohol] The characteristics of the polyvinyl alcohol of the present invention are: the saponification degree is 70 mol% or more and less than 99.9 mol%, the viscosity average polymerization degree is 400 or more and less than 1800, and the end contains 0.05 mol% or more and less than 0.5 mol% aldehyde groups , And the absorbance at 280 nm of the 0.1% by mass aqueous solution is 0.17 or more and less than 0.55.
PVA之皂化度為70莫耳%以上小於99.9莫耳%係屬重要。當使用皂化度小於70莫耳%的PVA作為交聯物之原料時,所得之交聯物之耐水性降低。當使用作為交聯物之原料時,PVA之皂化度係以80莫耳%以上為較佳,90莫耳%以上為更佳。另一方面,皂化度為99.9莫耳%以上的PVA係難以生產。It is important that the saponification degree of PVA is more than 70 mol% and less than 99.9 mol%. When PVA with a saponification degree of less than 70 mol% is used as the raw material of the cross-linked product, the water resistance of the obtained cross-linked product decreases. When used as a raw material for cross-linked products, the degree of saponification of PVA is preferably 80 mol% or more, and more preferably 90 mol% or more. On the other hand, it is difficult to produce PVA systems with a saponification degree of 99.9 mol% or more.
又,當使用皂化度小於70莫耳%的PVA作為乙烯基化合物之懸浮聚合用分散穩定劑時,聚合穩定性降低,而在所得之乙烯系樹脂中粗大粒子增加的同時,無法得到直徑一致的粒子。又,於所得之乙烯系樹脂大量產生魚眼。另一方面,皂化度為99.9莫耳%以上的PVA係難以製造。當使用作為乙烯基化合物之懸浮聚合用分散穩定劑時,PVA之皂化度係以小於90莫耳%為較佳,小於85莫耳%為更佳,小於80莫耳%為進一步較佳。皂化度係根據JIS K 6726:1994而測定所得之值。In addition, when PVA with a degree of saponification of less than 70 mol% is used as a dispersion stabilizer for suspension polymerization of vinyl compounds, the polymerization stability is reduced, and the resulting vinyl resin increases in coarse particles and cannot obtain uniform diameters. particle. In addition, a large amount of fish eyes are produced in the obtained vinyl resin. On the other hand, it is difficult to manufacture a PVA system having a saponification degree of 99.9 mol% or more. When used as a dispersion stabilizer for suspension polymerization of vinyl compounds, the degree of saponification of PVA is preferably less than 90 mol%, more preferably less than 85 mol%, and even more preferably less than 80 mol%. The degree of saponification is a value measured in accordance with JIS K 6726:1994.
PVA之黏度平均聚合度(以下有時簡略記載為聚合度)為400以上小於1800係屬重要。當使用聚合度小於400的PVA作為交聯物之原料時,所得之交聯物之耐水性降低。當使用作為交聯物之原料時,PVA之聚合度係以550以上為較佳。另一方面,當聚合度為1800以上時,PVA之生產性降低。又,當使用聚合度為1800以上的PVA作為交聯物之原料時,液體之黏度變得過高而操作性降低。PVA之聚合度係以小於1600為較佳。It is important that the viscosity average degree of polymerization of PVA (hereinafter sometimes referred to as the degree of polymerization) is more than 400 and less than 1800. When PVA with a degree of polymerization of less than 400 is used as the raw material of the cross-linked product, the water resistance of the obtained cross-linked product decreases. When used as a raw material for cross-linked products, the degree of polymerization of PVA is preferably 550 or more. On the other hand, when the degree of polymerization is 1800 or more, the productivity of PVA decreases. In addition, when PVA with a degree of polymerization of 1800 or higher is used as the raw material of the cross-linked product, the viscosity of the liquid becomes too high and the handleability decreases. The degree of polymerization of PVA is preferably less than 1600.
又,當使用聚合度小於400的PVA作為乙烯基化合物之懸浮聚合用分散穩定劑時,聚合穩定性降低,而在所得之乙烯系樹脂中粗大粒子增加的同時,無法得到直徑一致的粒子。PVA之聚合度係以550以上為較佳。另一方面,當聚合度為1800以上時,PVA之生產性降低。又,當使用聚合度為1800以上的PVA作為乙烯基化合物之懸浮聚合用分散穩定劑時,聚合穩定性降低,而在所得之乙烯系樹脂中粗大粒子增加的同時,無法得到直徑一致的粒子。又,於所得之乙烯系樹脂大量產生魚眼。當使用作為乙烯基化合物之懸浮聚合用分散穩定劑時,PVA之聚合度係以小於1500為較佳,小於1300為更佳,小於1000為進一步較佳。In addition, when PVA with a degree of polymerization of less than 400 is used as a dispersion stabilizer for suspension polymerization of a vinyl compound, the polymerization stability is reduced, and the resulting vinyl resin increases in coarse particles, and particles of uniform diameter cannot be obtained. The degree of polymerization of PVA is preferably 550 or more. On the other hand, when the degree of polymerization is 1800 or more, the productivity of PVA decreases. In addition, when PVA with a degree of polymerization of 1800 or higher is used as a dispersion stabilizer for suspension polymerization of a vinyl compound, the polymerization stability is reduced, and the resulting vinyl resin increases in coarse particles, and particles with uniform diameter cannot be obtained. In addition, a large amount of fish eyes are produced in the obtained vinyl resin. When used as a dispersion stabilizer for suspension polymerization of vinyl compounds, the degree of polymerization of PVA is preferably less than 1500, more preferably less than 1300, and even more preferably less than 1000.
黏度平均聚合度係根據JIS K 6726:1994而測定所得之值。具體而言,當皂化度小於99.5莫耳%時,係針對皂化至皂化度成為99.5莫耳%以上之PVA,使用在水中、30℃下測定之極限黏度[η](L/g),藉由下式而求出黏度平均聚合度(P)。 P=([η]×104 /8.29)(1/0.62) The viscosity average degree of polymerization is a value measured in accordance with JIS K 6726:1994. Specifically, when the degree of saponification is less than 99.5 mol%, the ultimate viscosity [η] (L/g) measured in water at 30°C is used for PVA saponified to a degree of saponification of 99.5 mol% or more. The viscosity average degree of polymerization (P) is obtained from the following formula. P=([η]×10 4 /8.29) (1/0.62)
本發明之PVA於末端含有0.05莫耳%以上小於0.5莫耳%的醛基係屬重要。醛基係反應活性的官能基,可利用於因與羥基之縮醛化所致之交聯反應、因自由基反應所致之交聯等。又,具有醛基之PVA由於對於乙烯基化合物之吸附力高,因此在使用作為乙烯基化合物之懸浮聚合用分散穩定劑時聚合係穩定,且在所得之乙烯系樹脂中粗大粒子及微粉之形成變少。再者,在將所得之乙烯系樹脂作成薄片狀時,亦可降低魚眼之產生。It is important that the PVA of the present invention contains more than 0.05 mol% and less than 0.5 mol% of aldehyde groups at the end. The aldehyde group is a reactive functional group that can be used for crosslinking reaction due to acetalization with hydroxyl group, crosslinking due to free radical reaction, etc. In addition, the PVA with aldehyde groups has a high adsorption force for vinyl compounds, so when it is used as a dispersion stabilizer for suspension polymerization of vinyl compounds, the polymerization system is stable, and coarse particles and fine powders are formed in the resulting vinyl resin Fewer. Furthermore, when the obtained vinyl resin is made into a sheet shape, the generation of fish eyes can also be reduced.
當使用醛基之含量小於0.05莫耳%的PVA作為交聯物之原料時,所得之交聯物之耐水性降低。醛基之含量係以0.08莫耳%以上為較佳。另一方面,醛基之含量為0.5莫耳%以上的PVA係生產性低。又,當使用這樣的PVA作為交聯物之原料時,液體之黏度變得過高而操作性降低。醛基之含量係以小於0.45莫耳%為較佳,小於0.4莫耳%為更佳。When PVA with an aldehyde group content of less than 0.05 mol% is used as the raw material of the cross-linked product, the water resistance of the obtained cross-linked product is reduced. The content of aldehyde groups is preferably 0.08 mol% or more. On the other hand, the PVA system with an aldehyde group content of 0.5 mol% or more has low productivity. In addition, when such PVA is used as a raw material for a cross-linked product, the viscosity of the liquid becomes too high and the handleability decreases. The content of aldehyde groups is preferably less than 0.45 mol%, more preferably less than 0.4 mol%.
又,當使用醛基之含量小於0.05莫耳%的PVA作為乙烯基化合物之懸浮聚合用分散穩定劑時,聚合穩定性降低,而在所得之乙烯系樹脂中粗大粒子增加的同時,無法得到直徑一致的粒子。又,於所得之乙烯系樹脂大量產生魚眼。醛基之含量係以0.08莫耳%以上為較佳。另一方面,醛基之含量為0.5莫耳%以上的PVA係生產性低。又,當使用這樣的PVA作為乙烯基化合物之懸浮聚合用分散穩定劑時,聚合穩定性降低,而在所得之乙烯系樹脂中粗大粒子增加的同時,無法得到直徑一致的粒子。又,於所得之乙烯系樹脂大量產生魚眼。醛基之含量係以小於0.45莫耳%為較佳,小於0.4莫耳%為更佳。醛基之含量可從皂化前的乙烯酯系聚合物之在氘代氯仿溶劑中的1 H-NMR光譜、或是PVA之在重DMSO或重水溶劑中的1 H-NMR光譜來求出。In addition, when PVA with an aldehyde group content of less than 0.05 mol% is used as a dispersion stabilizer for suspension polymerization of a vinyl compound, the polymerization stability is reduced, and the resulting vinyl resin has an increase in coarse particles, and the diameter cannot be obtained. Consistent particles. In addition, a large amount of fish eyes are produced in the obtained vinyl resin. The content of aldehyde groups is preferably 0.08 mol% or more. On the other hand, the PVA system with an aldehyde group content of 0.5 mol% or more has low productivity. In addition, when such PVA is used as a dispersion stabilizer for suspension polymerization of a vinyl compound, the polymerization stability is reduced, and the resulting vinyl resin increases in coarse particles, and particles of uniform diameter cannot be obtained. In addition, a large amount of fish eyes are produced in the obtained vinyl resin. The content of aldehyde groups is preferably less than 0.45 mol%, more preferably less than 0.4 mol%. The aldehyde content can be in deuterated chloroform solvent 1 H-NMR spectrum of the polymer from the vinyl ester before saponification of PVA in a heavy or heavy water or DMSO solvent 1 H-NMR spectrum is obtained.
本發明之PVA亦可含有醛基以外的官能基,但其含量係以小於5莫耳%為較佳,小於1莫耳%為更佳,小於0.1莫耳%為進一步較佳。The PVA of the present invention may also contain functional groups other than aldehyde groups, but its content is preferably less than 5 mol%, more preferably less than 1 mol%, and even more preferably less than 0.1 mol%.
PVA之0.1質量%水溶液之280nm的吸光度為0.17以上小於0.55係屬重要。當使用上述吸光度小於0.17的PVA作為交聯物之原料時,所得之交聯物之耐水性降低。上述吸光度係以0.21以上為較佳,0.24以上為更佳,0.28以上為進一步較佳。另一方面,上述吸光度為0.55以上的PVA係生產性低。又,當使用這樣的PVA作為交聯物之原料時,液體之黏度變得過高而操作性降低。上述吸光度係以小於0.52為較佳,小於0.48為更佳,小於0.45為進一步較佳。It is important that the absorbance at 280 nm of a 0.1% by mass aqueous solution of PVA is 0.17 or more and less than 0.55. When the above-mentioned PVA with an absorbance of less than 0.17 is used as the raw material of the cross-linked product, the water resistance of the obtained cross-linked product decreases. The above-mentioned absorbance is preferably 0.21 or more, more preferably 0.24 or more, and even more preferably 0.28 or more. On the other hand, the above-mentioned PVA-based absorbance of 0.55 or more has low productivity. In addition, when such PVA is used as a raw material for a cross-linked product, the viscosity of the liquid becomes too high and the handleability decreases. The above-mentioned absorbance is preferably less than 0.52, more preferably less than 0.48, and even more preferably less than 0.45.
又,當使用上述吸光度小於0.17的PVA作為乙烯基化合物之懸浮聚合用分散穩定劑時,聚合穩定性降低,而在所得之乙烯系樹脂中粗大粒子增加的同時,無法得到直徑一致的粒子。又,於所得之乙烯系樹脂大量產生魚眼。上述吸光度係以0.21以上為較佳,0.24以上為更佳,0.28以上為進一步較佳。另一方面,上述吸光度為0.55以上的PVA係生產性低。又,當使用這樣的PVA作為乙烯基化合物之懸浮聚合用分散穩定劑時,聚合穩定性降低,而在所得之乙烯系樹脂中粗大粒子增加的同時,無法得到直徑一致的粒子。又,於所得之乙烯系樹脂大量產生魚眼。上述吸光度係以小於0.52為較佳,小於0.48為更佳,小於0.45為進一步較佳。In addition, when the above-mentioned PVA having an absorbance of less than 0.17 is used as a dispersion stabilizer for suspension polymerization of a vinyl compound, the polymerization stability is reduced, and the resulting vinyl resin increases in coarse particles, and particles of uniform diameter cannot be obtained. In addition, a large amount of fish eyes are produced in the obtained vinyl resin. The above-mentioned absorbance is preferably 0.21 or more, more preferably 0.24 or more, and even more preferably 0.28 or more. On the other hand, the above-mentioned PVA-based absorbance of 0.55 or more has low productivity. In addition, when such PVA is used as a dispersion stabilizer for suspension polymerization of a vinyl compound, the polymerization stability is reduced, and the resulting vinyl resin increases in coarse particles, and particles of uniform diameter cannot be obtained. In addition, a large amount of fish eyes are produced in the obtained vinyl resin. The above-mentioned absorbance is preferably less than 0.52, more preferably less than 0.48, and even more preferably less than 0.45.
上述吸光度表示存在於PVA之主鏈的乙烯性雙鍵之量或鏈。藉由吸光度在上述的範圍內,而在PVA與乙烯基化合物之吸附性提升的同時,藉由與PVA之末端的醛基之相乘效果,而使用作為乙烯基化合物之懸浮聚合用分散穩定劑時的聚合穩定性更進一步提升。當使用吸光度在上述的範圍內之PVA作為交聯物之原料時,所得之交聯物之耐水性提升。此外,波長280nm之吸收係源自PVA中的[-CO-(CH=CH)2 -]之結構。本結構之導入可藉由作為改性劑而使用醛類、或使用可藉由共聚合而於主鏈導入乙烯性雙鍵之單體等而達成。當吸光度在上述範圍外時,PVA與乙烯基化合物之吸附力降低、或PVA與乙烯基化合物成為溶解狀態。因此,變得無法發揮作為懸浮聚合用分散穩定劑之效果。又,當使用吸光度在上述範圍外的PVA作為交聯物之原料時,所得之交聯物之耐水性降低。吸光度之測定裝置等條件係如後述的實施例所記載。The above-mentioned absorbance indicates the amount or chain of ethylenic double bonds present in the main chain of PVA. With the absorbance within the above range, the adsorption of PVA and vinyl compounds is improved, and the synergistic effect with the aldehyde group at the end of the PVA is used as a dispersion stabilizer for suspension polymerization of vinyl compounds When the polymerization stability is further improved. When PVA with an absorbance in the above range is used as the raw material of the cross-linked product, the water resistance of the obtained cross-linked product is improved. In addition, the absorption at a wavelength of 280 nm is derived from the structure of [-CO-(CH=CH) 2 -] in PVA. The introduction of this structure can be achieved by using an aldehyde as a modifier, or by using a monomer that can introduce an ethylenic double bond into the main chain by copolymerization. When the absorbance is outside the above range, the adsorption force of PVA and the vinyl compound is reduced, or the PVA and the vinyl compound are in a dissolved state. Therefore, it becomes impossible to exert the effect as a dispersion stabilizer for suspension polymerization. In addition, when PVA having an absorbance outside the above-mentioned range is used as the raw material of the cross-linked product, the water resistance of the obtained cross-linked product decreases. The conditions such as the absorbance measuring device are as described in the examples described later.
本發明之PVA係以於末端具有下述式(1)所表示之結構為較佳。The PVA of the present invention preferably has a structure represented by the following formula (1) at the end.
(式(1)中,X表示單鍵、可具有取代基之伸烷基或可具有取代基之伸芳基,*表示鍵結鍵)。 (In formula (1), X represents a single bond, an alkylene group which may have a substituent or an arylene group which may have a substituent, and * represents a bonding bond).
式(1)中,X為單鍵、可具有取代基之伸烷基或可具有取代基之伸芳基。X之碳數係以0~8為較佳,1~6為更佳,1~4為進一步較佳,2~4為特佳,3~4為最佳。X係以具有上述碳數之伸烷基或伸芳基為較佳,具有上述碳數之伸烷基為更佳。X滿足上述態樣時,具有下述傾向:容易導入PVA之醛基、所得之PVA之水溶性良好、使用PVA作為乙烯基化合物之懸浮聚合用分散穩定劑時的聚合穩定性良好、或可在所得之乙烯系樹脂中抑制魚眼之產生。In the formula (1), X is a single bond, an alkylene group which may have a substituent, or an arylene group which may have a substituent. The carbon number of X is preferably from 0 to 8, more preferably from 1 to 6, more preferably from 1 to 4, particularly preferably from 2 to 4, and most preferably from 3 to 4. X is preferably an alkylene group or arylene group having the above-mentioned carbon number, and more preferably an alkylene group having the above-mentioned carbon number. When X satisfies the above conditions, it has the following tendency: it is easy to introduce the aldehyde group of PVA, the water solubility of the obtained PVA is good, the polymerization stability when PVA is used as a dispersion stabilizer for suspension polymerization of a vinyl compound is good, or In the obtained vinyl resin, the production of fish eyes is suppressed.
作為前述伸烷基或伸芳基可具有之取代基,可列舉:烷基、芳基、羥基、醛基、羧基、胺基等。Examples of the substituent that the aforementioned alkylene group or arylene group may have include an alkyl group, an aryl group, a hydroxyl group, an aldehyde group, a carboxyl group, and an amino group.
(PVA之製造方法) 本發明之PVA之製造方法並未特別限定,而理想的製造方法係在二醛或三醛之存在下使乙烯酯聚合而得到聚乙烯酯後,將該聚乙烯酯皂化之方法。(Method of manufacturing PVA) The manufacturing method of the PVA of the present invention is not particularly limited, and an ideal manufacturing method is a method of saponifying the polyvinyl ester after polymerizing vinyl ester in the presence of dialdehyde or trialdehyde to obtain polyvinyl ester.
作為聚合方法,可列舉:塊狀聚合法、溶液聚合法、懸浮聚合法、乳化聚合法、分散聚合法等周知的方法,從工業上的觀點來看,以溶液聚合法、乳化聚合法及分散聚合法為較佳。關於聚合操作,則分批法、半分批法及連續法之任一方式皆可採用。Examples of polymerization methods include: block polymerization, solution polymerization, suspension polymerization, emulsion polymerization, dispersion polymerization, and other well-known methods. From an industrial point of view, solution polymerization, emulsion polymerization, and dispersion The polymerization method is preferred. Regarding the polymerization operation, any of a batch method, a semi-batch method, and a continuous method can be adopted.
作為乙烯酯,可列舉例如:乙酸乙烯酯、甲酸乙烯酯、丙酸乙烯酯、辛酸乙烯酯、維沙狄克酸乙烯酯(Vinyl versatate)等,從工業上的觀點來看,其中又以乙酸乙烯酯為較佳。Examples of vinyl esters include vinyl acetate, vinyl formate, vinyl propionate, vinyl octanoate, Vinyl versatate, etc. From an industrial point of view, among them, acetic acid is used. Vinyl ester is preferred.
二醛或三醛之種類並未特別限定,可列舉:乙二醛、丙二醛、丁二醛、戊二醛、己二醛、庚二醛、辛二醛、壬二醛、苯三甲醛等。其中,從容易導入醛基、所得之PVA之水溶性良好、使用PVA作為乙烯基化合物之懸浮聚合用分散穩定劑時的聚合穩定性良好的觀點來看,又可理想地使用碳數2~10之二醛或三醛,可更理想地使用碳數2~6之二醛。從容易得到、可在所得之乙烯系樹脂中抑制魚眼之產生的觀點來看,可進一步理想地使用戊二醛。二醛或三醛之使用量,係相對於乙烯酯100質量份,而以0.5質量份以上為較佳,1質量份以上為更佳。另一方面,二醛或三醛之使用量,係相對於乙烯酯100質量份,而以10質量份以下為較佳,5質量份以下為更佳。二醛或三醛可單獨使用一種,亦可併用二種以上。The type of dialdehyde or trialdehyde is not particularly limited, and examples include: glyoxal, malondialdehyde, succinic aldehyde, glutaraldehyde, adipaldehyde, pimelic aldehyde, suberaldehyde, azelaaldehyde, and trimelliformaldehyde Wait. Among them, from the viewpoints of easy introduction of aldehyde groups, good water solubility of the obtained PVA, and good polymerization stability when PVA is used as a dispersion stabilizer for suspension polymerization of a vinyl compound, it is also desirable to use a carbon number of 2 to 10 The dialdehyde or trialdehyde, the dialdehyde with 2-6 carbons can be more ideally used. From the viewpoint of easy availability and suppression of fisheyes in the obtained vinyl resin, glutaraldehyde can be more preferably used. The amount of dialdehyde or trialdehyde used is preferably 0.5 parts by mass or more, and more preferably 1 part by mass or more with respect to 100 parts by mass of vinyl ester. On the other hand, the amount of dialdehyde or trialdehyde used is preferably 10 parts by mass or less, and more preferably 5 parts by mass or less with respect to 100 parts by mass of vinyl ester. One kind of dialdehyde or trialdehyde may be used alone, or two or more kinds may be used in combination.
以在聚合步驟中使用溶劑,且乙烯酯與溶劑之質量比為乙烯酯/溶劑=100/0~90/10為較佳。若乙烯酯與溶劑之質量比大於90/10,則當使用PVA作為乙烯基化合物之懸浮聚合用分散穩定劑時,有作為分散穩定劑之性能降低的傾向。Preferably, a solvent is used in the polymerization step, and the mass ratio of vinyl ester to solvent is vinyl ester/solvent=100/0 to 90/10. If the mass ratio of vinyl ester to solvent is greater than 90/10, when PVA is used as a dispersion stabilizer for suspension polymerization of vinyl compounds, the performance as a dispersion stabilizer tends to decrease.
在聚合步驟中,可在未損及本發明之旨趣的範圍,共聚合乙烯酯以外的其它單體。藉由將其它單體與乙烯酯共聚合,於所得之聚合物的主鏈中具有其它單體單元之結構。作為該其它單體,可列舉例如:乙烯、丙烯等α-烯烴類;(甲基)丙烯酸及其鹽;(甲基)丙烯酸甲酯、(甲基)丙烯酸乙酯、(甲基)丙烯酸正丙酯、(甲基)丙烯酸異丙酯、(甲基)丙烯酸正丁酯、(甲基)丙烯酸異丁酯、(甲基)丙烯酸三級丁酯、(甲基)丙烯酸2-乙基己酯、(甲基)丙烯酸十二酯、(甲基)丙烯酸十八酯等(甲基)丙烯酸酯類;(甲基)丙烯醯胺;N-甲基(甲基)丙烯醯胺、N-乙基(甲基)丙烯醯胺、N,N-二甲基(甲基)丙烯醯胺、二丙酮(甲基)丙烯醯胺、(甲基)丙烯醯胺丙磺酸及其鹽、(甲基)丙烯醯胺丙基二甲基胺及其鹽或其四級鹽、N-羥甲基(甲基)丙烯醯胺及其衍生物等(甲基)丙烯醯胺衍生物;甲基乙烯醚、乙基乙烯醚、正丙基乙烯醚、異丙基乙烯醚、正丁基乙烯醚、異丁基乙烯醚、三級丁基乙烯醚、十二基乙烯醚、十八基乙烯醚等乙烯醚類;丙烯腈、甲基丙烯腈等腈類;氯乙烯、氟乙烯等鹵化乙烯類;偏二氯乙烯、偏二氟乙烯等鹵化亞乙烯類;乙酸烯丙酯、氯丙烯等烯丙基化合物;馬來酸、伊康酸、富馬酸等不飽和二羧酸及其鹽或其酯;乙烯基三甲氧基矽烷等乙烯基矽基化合物;乙酸異丙烯酯等。當共聚合這樣的其它單體時,其含有率通常為5莫耳%以下。In the polymerization step, it is possible to copolymerize other monomers other than vinyl ester within a range that does not impair the purpose of the present invention. By copolymerizing other monomers with vinyl esters, the resulting polymer has a structure of other monomer units in the main chain. Examples of the other monomers include α-olefins such as ethylene and propylene; (meth)acrylic acid and its salts; methyl (meth)acrylate, ethyl (meth)acrylate, and (meth)acrylic acid Propyl ester, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tertiary butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate (Meth)acrylates such as esters, lauryl (meth)acrylate, stearyl (meth)acrylate, etc.; (meth)acrylamide; N-methyl(meth)acrylamide, N- Ethyl (meth)acrylamide, N,N-dimethyl (meth)acrylamide, diacetone (meth)acrylamide, (meth)acrylamide propanesulfonic acid and its salts, ( (Meth)acrylamide propyldimethylamine and its salt or its quaternary salt, N-methylol (meth)acrylamide and its derivatives and other (meth)acrylamide derivatives; methyl Vinyl ether, ethyl vinyl ether, n-propyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether, tertiary butyl vinyl ether, dodecyl vinyl ether, octadecyl vinyl ether Vinyl ethers; Nitriles such as acrylonitrile and methacrylonitrile; Vinyl halide such as vinyl chloride and vinyl fluoride; Halogenated vinylidene such as vinylidene chloride and vinylidene fluoride; Allyl acetate, propylene chloride and other olefins Propyl compounds; unsaturated dicarboxylic acids such as maleic acid, itaconic acid, and fumaric acid and their salts or esters thereof; vinyl silyl compounds such as vinyl trimethoxysilane; isopropenyl acetate, etc. When such other monomers are copolymerized, their content is usually 5 mol% or less.
作為使用於聚合步驟之溶劑,係以醇系溶劑為較佳。作為醇系溶劑,可列舉例如:甲醇、乙醇、丙醇等,其中又以甲醇為較佳。此等可單獨使用1種,或併用2種以上。As the solvent used in the polymerization step, an alcohol-based solvent is preferred. Examples of the alcohol-based solvent include methanol, ethanol, propanol, and the like. Among them, methanol is preferred. These can be used individually by 1 type or in combination of 2 or more types.
在本發明之製造方法中,係以在二醛或三醛、及水之存在下使乙烯酯聚合而得到聚乙烯酯後,將該聚乙烯酯皂化之方法為更理想。此時的水之質量,係以二醛或三醛之量的0.3倍以上為較佳,0.4倍以上為更佳。另一方面,水之質量係以小於二醛或三醛之量的9倍為較佳,小於4倍為更佳,小於2倍為進一步較佳。In the production method of the present invention, a method of polymerizing vinyl ester in the presence of dialdehyde or trialdehyde and water to obtain polyvinyl ester, and then saponifying the polyvinyl ester is more preferable. The quality of water at this time is preferably 0.3 times or more of the amount of dialdehyde or trialdehyde, and more preferably 0.4 times or more. On the other hand, the quality of water is preferably less than 9 times the amount of dialdehyde or trialdehyde, more preferably less than 4 times, and more preferably less than 2 times.
通常因添加水而聚合步驟及接續其之皂化步驟之生產性降低,但在本發明中,發現了藉由添加水而可輕易地在末端導入醛結構。該理由並不確定,但推測是因為:藉由添加水,而聚合步驟中的二醛或三醛之副反應(半縮醛、縮醛化、環化)被抑制,化學平衡比起因副反應所致之生成物的狀態,更傾向醛的狀態,因此二醛或三醛與乙烯酯之反應會有效率地進行。Generally, the productivity of the polymerization step and the subsequent saponification step is reduced due to the addition of water. However, in the present invention, it has been discovered that by adding water, an aldehyde structure can be easily introduced at the end. The reason for this is not certain, but it is presumed to be because the side reactions (hemiacetal, acetalization, cyclization) of the dialdehyde or trialdehyde in the polymerization step are suppressed by adding water, and the chemical equilibrium is more than caused by side reactions. The resulting state of the product tends to be more aldehyde state, so the reaction between dialdehyde or trialdehyde and vinyl ester will proceed efficiently.
使用於聚合步驟之聚合起始劑並未特別限定,可因應聚合方法而選自周知的聚合起始劑。作為聚合起始劑,可列舉例如:偶氮系聚合起始劑、過氧化物系聚合起始劑、氧化還原系聚合起始劑等。作為偶氮系聚合起始劑,可列舉例如:2,2’-偶氮雙(2,4-二甲基戊腈)、2,2’-偶氮雙(異丁腈)、2,2’-偶氮雙(4-甲氧基-2,4-二甲基戊腈)等。過氧化物系聚合起始劑可列舉例如:過氧二碳酸二異丙酯、過氧二碳酸二(2-乙基己)酯、過氧二碳酸二乙氧基乙酯等過碳酸酯系化合物;過氧新癸酸三級丁酯、過氧新癸酸異丙苯酯等過氧酸酯化合物;過氧化乙醯基環己基碸基;2,4,4-三甲基戊基-2-過氧苯氧乙酸酯等。作為氧化還原系聚合起始劑,可使用組合氧化劑與還原劑者。作為氧化劑,係以過氧化物為較佳。作為還原劑,可列舉:金屬離子、還原性化合物等。作為氧化劑與還原劑之組合,可列舉:過氧化物與金屬離子之組合;過氧化物與還原性化合物之組合;過氧化物、與金屬離子及還原性化合物之組合等。作為過氧化物,可列舉:過氧化氫、氫過氧化異丙苯、氫過氧化三級丁基等氫過氧化物、過硫酸鹽(鉀、鈉或銨鹽)、過乙酸三級丁酯、過酸酯(過氧苯甲酸三級丁酯)等。作為金屬離子,可列舉:Fe2+ 、Cr2+ 、V2+ 、Co2+ 、Ti3+ 、Cu+ 等可接受1電子移動之金屬離子。作為還原性化合物,可列舉:亞硫酸氫鈉、碳酸氫鈉、酒石酸、果糖、葡萄糖、山梨糖、肌醇、吊白塊、抗壞血酸。此等之中,又以選自包含過氧化氫、過硫酸鉀、過硫酸鈉及過硫酸銨之群組的1種以上的過氧化物、與選自包含亞硫酸氫鈉、碳酸氫鈉、酒石酸、吊白塊及抗壞血酸之群組的1種以上的還原劑之組合為較佳,過氧化氫與選自包含亞硫酸氫鈉、碳酸氫鈉、酒石酸、吊白塊及抗壞血酸之群組的1種以上的還原劑之組合為更佳。又,可將過硫酸鉀、過硫酸銨、過氧化氫、氫過氧化異丙苯等水溶性之聚合起始劑與上述聚合起始劑組合而作成聚合起始劑。此等聚合起始劑可單獨使用1種,或併用2種以上。The polymerization initiator used in the polymerization step is not particularly limited, and can be selected from well-known polymerization initiators according to the polymerization method. Examples of the polymerization initiator include azo polymerization initiators, peroxide polymerization initiators, redox polymerization initiators, and the like. As the azo polymerization initiator, for example, 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(isobutyronitrile), 2,2 '-Azobis(4-methoxy-2,4-dimethylvaleronitrile) and the like. Examples of peroxide-based polymerization initiators include percarbonate systems such as diisopropyl peroxydicarbonate, bis(2-ethylhexyl)peroxydicarbonate, and diethoxyethyl peroxydicarbonate. Compounds; peroxyester compounds such as tertiary butyl peroxyneodecanoate and cumyl peroxyneodecanoate; acetyl cyclohexyl peroxyl; 2,4,4-trimethylpentyl- 2-Peroxyphenoxyacetate, etc. As the redox polymerization initiator, a combination of an oxidizing agent and a reducing agent can be used. As the oxidant, peroxide is preferred. As a reducing agent, a metal ion, a reducing compound, etc. are mentioned. As a combination of an oxidizing agent and a reducing agent, a combination of a peroxide and a metal ion; a combination of a peroxide and a reducing compound; a combination of a peroxide, a metal ion and a reducing compound, and the like. Examples of peroxides include hydroperoxides such as hydrogen peroxide, cumene hydroperoxide, and tertiary butyl hydroperoxide, persulfates (potassium, sodium, or ammonium salt), and tertiary butyl peracetic acid. , Perester (tertiary butyl peroxybenzoate) and so on. Examples of metal ions include metal ions that can move one electron , such as Fe 2+ , Cr 2+ , V 2+ , Co 2+ , Ti 3+ , and Cu +. Examples of the reducing compound include sodium bisulfite, sodium bicarbonate, tartaric acid, fructose, glucose, sorbose, inositol, white lump, and ascorbic acid. Among these, one or more peroxides selected from the group consisting of hydrogen peroxide, potassium persulfate, sodium persulfate and ammonium persulfate, and selected from the group consisting of sodium bisulfite, sodium bicarbonate, The combination of more than one reducing agent from the group of tartaric acid, tartaric acid, and ascorbic acid is preferred. A combination of more than one reducing agent is more preferable. In addition, a water-soluble polymerization initiator such as potassium persulfate, ammonium persulfate, hydrogen peroxide, and cumene hydroperoxide can be combined with the above-mentioned polymerization initiator to form a polymerization initiator. These polymerization initiators can be used singly or in combination of two or more.
在二醛或三醛之存在下使乙烯酯聚合時,該乙烯酯之聚合率並未特別限定,但以10%以上小於90%為較佳。當聚合率小於10%時,有PVA之生產性降低之虞。聚合率係以20%以上為更佳。另一方面,當聚合率為90%以上時,有發生所得之聚乙烯酯之黏度變得過高而PVA之生產性降低、所得之PVA之色相惡化等問題之虞。聚合率係以小於70%為更佳。When the vinyl ester is polymerized in the presence of dialdehyde or trialdehyde, the polymerization rate of the vinyl ester is not particularly limited, but it is preferably 10% or more and less than 90%. When the polymerization rate is less than 10%, the productivity of PVA may decrease. The polymerization rate is more preferably 20% or more. On the other hand, when the polymerization rate is 90% or more, the viscosity of the obtained polyvinyl ester may become too high, the productivity of PVA may decrease, and the hue of the obtained PVA may deteriorate. The polymerization rate is preferably less than 70%.
將聚乙烯酯皂化之方法並未特別限定,可採用周知的皂化方法。可列舉例如:使用了氫氧化鈉、氫氧化鉀、甲氧鈉等鹼性觸媒、對甲苯磺酸等酸性觸媒之醇解反應或水解反應。作為可使用於該反應之溶劑,可列舉例如:甲醇、乙醇等醇類;乙酸甲酯、乙酸乙酯等酯類;丙酮、甲基乙基酮等酮類:苯、甲苯等芳香族烴等。此等溶劑可單獨使用1種,或併用2種以上。其中,又以將甲醇或甲醇/乙酸甲酯混合溶液作為溶劑,且將氫氧化鈉作為觸媒而皂化之方法為簡便而為較佳。The method of saponifying polyvinyl ester is not particularly limited, and a well-known saponification method can be used. Examples include alcoholysis or hydrolysis using alkaline catalysts such as sodium hydroxide, potassium hydroxide, and sodium methoxide, and acid catalysts such as p-toluenesulfonic acid. Examples of solvents that can be used in this reaction include alcohols such as methanol and ethanol; esters such as methyl acetate and ethyl acetate; ketones such as acetone and methyl ethyl ketone; aromatic hydrocarbons such as benzene and toluene. . These solvents can be used alone or in combination of two or more. Among them, the method of saponification using methanol or a methanol/methyl acetate mixed solution as a solvent and sodium hydroxide as a catalyst is simple and preferred.
(用途) 本發明之PVA可使用於各種用途。以下列舉其例但不限定於此。 (1)分散劑用途:塗料、接著劑等顏料之分散穩定劑、氯乙烯、偏二氯乙烯、苯乙烯、(甲基)丙烯酸酯、乙酸乙烯酯等各種乙烯基化合物之懸浮聚合用分散穩定劑及分散助劑 (2)被覆劑用途:紙之塗布劑、上漿劑、纖維加工劑、皮革整飾劑、塗料、防霧劑、抗金屬腐蝕劑、鍍鋅用光澤劑、抗靜電劑、醫藥被覆劑 (3)接著劑用途:接著劑、黏著劑、再濕接著劑、各種黏合劑、水泥和砂漿用添加劑 (4)乳化劑用途:乳化聚合用乳化劑、瀝青等後乳化劑 (5)凝集劑用途:水中懸浮物及溶存物之凝集劑、金屬凝集劑 (6)紙加工用途:紙力增強劑、耐油・耐溶劑賦予劑、平滑性提升劑、表面光澤改良助劑、塗封劑、阻隔劑、耐光性賦予劑、耐水化劑、染料・顯色劑分散劑、接著力改良劑、黏合劑 (7)農業用途:農藥用黏合劑、農藥用展布劑、農業用被覆劑、土壤改良劑、抗侵蝕劑、農藥用分散劑 (8)醫療・化妝品用途:造粒黏合劑、塗布劑、乳化劑、貼附劑、結合劑、薄膜製劑基材、皮膜形成劑 (9)黏度調整劑用途:增黏劑、流變調整劑 (10)薄膜用途:水溶性薄膜、偏光薄膜、阻隔膜、纖維製品包裝用薄膜、種子養護薄片、植生薄片、種子帶、吸濕性薄膜 (11)成形物用途:纖維、管(pipe)、管(tube)、防漏膜、水溶蕾絲(chemical lace)用水溶性纖維、海綿 (12)凝膠用途:醫藥用凝膠、工業用凝膠 (13)後反應用途:與低分子有機化合物、高分子有機化合物、無機化合物之後反應用途 本發明之PVA藉由使用酸觸媒,而分子鏈之活動被拘束於三次元方向,可合成比起同種的線狀高分子,更高黏度、高耐水性、高強度、耐熱性、耐溶劑性優異的交聯物。因此,可理想地使用於上述(2)被覆材用途、(3)接著劑用途、(10)薄膜用途、(12)凝膠用途等。又,本發明之PVA係如後述,亦可理想地使用於(1)分散劑用途。(use) The PVA of the present invention can be used for various purposes. Examples are listed below, but are not limited to them. (1) Dispersant use: dispersion stabilizer for pigments such as paints and adhesives, dispersion stabilizer for suspension polymerization of various vinyl compounds such as vinyl chloride, vinylidene chloride, styrene, (meth)acrylate, vinyl acetate, etc. Agent and dispersing aid (2) Coating agent use: paper coating agent, sizing agent, fiber processing agent, leather finishing agent, paint, anti-fogging agent, anti-metal corrosion agent, gloss agent for galvanizing, antistatic agent, pharmaceutical coating agent (3) Adhesive use: Adhesives, adhesives, rewetting adhesives, various adhesives, additives for cement and mortar (4) Use of emulsifier: emulsifier for emulsion polymerization, post-emulsifier such as asphalt (5) Application of aggregating agent: aggregating agent for suspended and dissolved substances in water, and metal aggregating agent (6) Paper processing applications: paper strength enhancer, oil and solvent resistance imparting agent, smoothness enhancer, surface gloss improvement auxiliary, coating agent, barrier agent, light resistance imparting agent, water resistance agent, dye and color development Dispersant, Adhesive Improver, Adhesive (7) Agricultural applications: Binders for pesticides, spreading agents for pesticides, agricultural coatings, soil conditioners, anti-erosion agents, and dispersants for pesticides (8) Medical and cosmetic applications: granulated adhesives, coating agents, emulsifiers, adhesives, bonding agents, film preparation substrates, film forming agents (9) Application of viscosity modifier: viscosity increasing agent, rheology modifier (10) Film application: water-soluble film, polarizing film, barrier film, film for packaging fiber products, seed care sheet, planting sheet, seed tape, hygroscopic film (11) Uses of molded products: fibers, pipes, tubes, leak-proof membranes, water-soluble fibers for chemical lace, sponges (12) Gel application: medical gel, industrial gel (13) Post-reaction applications: post-reaction applications with low molecular weight organic compounds, high molecular weight organic compounds, and inorganic compounds The PVA of the present invention uses an acid catalyst, and the movement of the molecular chain is restricted to the three-dimensional direction. Compared with the same kind of linear polymer, it can be synthesized with higher viscosity, high water resistance, high strength, heat resistance, and solvent resistance. A cross-linked product with excellent properties. Therefore, it can be ideally used for the above-mentioned (2) coating material use, (3) adhesive use, (10) film use, (12) gel use, and the like. In addition, the PVA of the present invention is described later, and can also be ideally used for (1) dispersant applications.
(乙烯基化合物之懸浮聚合用分散穩定劑) 本發明之PVA之理想的用途,係含有該PVA之乙烯基化合物之懸浮聚合用分散穩定劑。若使用本發明之PVA作為乙烯基化合物之懸浮聚合用分散穩定劑,則聚合反應穩定且可抑制粗大粒子及微粉之形成。又,可抑制將所得之乙烯系樹脂作成薄片狀時的魚眼之產生。(Dispersion stabilizer for suspension polymerization of vinyl compounds) The ideal application of the PVA of the present invention is a dispersion stabilizer for suspension polymerization of a vinyl compound containing the PVA. If the PVA of the present invention is used as a dispersion stabilizer for suspension polymerization of vinyl compounds, the polymerization reaction is stable and the formation of coarse particles and fine powder can be suppressed. In addition, it is possible to suppress the generation of fish eyes when the obtained vinyl resin is made into a sheet shape.
上述懸浮聚合用分散穩定劑,在未損及本發明之旨趣的範圍,亦可含有各種添加劑。作為上述添加劑,可列舉例如:醛類、鹵化烴類、硫醇類等聚合調節劑;苯酚化合物、硫化合物、N-氧化物化合物等聚合抑制劑;pH調整劑;交聯劑;防腐劑;防黴劑;抗嵌段劑;除泡劑;相溶化劑等。懸浮聚合用分散穩定劑中的各種添加劑之含量,係相對於懸浮聚合用分散穩定劑全體而以10質量%以下為較佳,5質量%以下為更佳。The aforementioned dispersion stabilizer for suspension polymerization may contain various additives within a range that does not impair the spirit of the present invention. Examples of the above additives include: polymerization regulators such as aldehydes, halogenated hydrocarbons, and mercaptans; polymerization inhibitors such as phenol compounds, sulfur compounds, and N-oxide compounds; pH regulators; crosslinking agents; preservatives; Anti-mold agent; anti-blocking agent; defoaming agent; compatibility agent, etc. The content of the various additives in the dispersion stabilizer for suspension polymerization is preferably 10% by mass or less, and more preferably 5% by mass or less with respect to the entire dispersion stabilizer for suspension polymerization.
(乙烯系樹脂之製造方法) 本發明之其它理想的實施態樣,係在本發明之PVA之存在下將乙烯基化合物懸浮聚合之乙烯系樹脂之製造方法。在該製造方法中,可得到粒子狀的乙烯系樹脂。(Manufacturing method of vinyl resin) Another ideal embodiment of the present invention is a method for producing a vinyl resin by suspension polymerization of a vinyl compound in the presence of the PVA of the present invention. In this production method, a particulate vinyl resin can be obtained.
作為將本發明之懸浮聚合用分散穩定劑投入聚合槽之方法,可列舉例如:(i)作成水溶液而投入聚合槽之方法、(ii)以粉末狀態直接投入之方法等。從在聚合槽內的均勻性的觀點來看,以上述(i)之方法為較佳。As a method of putting the dispersion stabilizer for suspension polymerization of the present invention into a polymerization tank, for example, (i) a method of preparing an aqueous solution and putting it into a polymerization tank, (ii) a method of directly putting it in a powder state, and the like. From the viewpoint of uniformity in the polymerization tank, the method of (i) above is preferred.
作為乙烯基化合物,可列舉:氯乙烯等鹵化乙烯;乙酸乙烯酯、丙酸乙烯酯等乙烯酯;丙烯酸、甲基丙烯酸、此等之酯及鹽;馬來酸、富馬酸、此等之酯及酐;苯乙烯、丙烯腈、偏二氯乙烯、乙烯醚等。其中,又以單獨使用氯乙烯,或併用氯乙烯及可與氯乙烯共聚合之單體為較佳。作為可與氯乙烯共聚合之單體,可列舉:乙酸乙烯酯、丙酸乙烯酯等乙烯酯;(甲基)丙烯酸甲酯、(甲基)丙烯酸乙酯等(甲基)丙烯酸酯;乙烯、丙烯等α-烯烴;馬來酸酐、伊康酸等不飽和二羧酸類;丙烯腈、苯乙烯、偏二氯乙烯、乙烯醚等。Examples of vinyl compounds include: vinyl halides such as vinyl chloride; vinyl esters such as vinyl acetate and vinyl propionate; esters and salts of acrylic acid, methacrylic acid, and the like; maleic acid, fumaric acid, and the like Esters and anhydrides; styrene, acrylonitrile, vinylidene chloride, vinyl ether, etc. Among them, it is preferable to use vinyl chloride alone or in combination with vinyl chloride and a monomer copolymerizable with vinyl chloride. Examples of monomers copolymerizable with vinyl chloride include vinyl esters such as vinyl acetate and vinyl propionate; (meth)acrylates such as methyl (meth)acrylate and ethyl (meth)acrylate; ethylene , Propylene and other α-olefins; maleic anhydride, itaconic acid and other unsaturated dicarboxylic acids; acrylonitrile, styrene, vinylidene chloride, vinyl ether, etc.
乙烯基化合物之懸浮聚合中,可使用以往使用於氯乙烯之聚合的油溶性或水溶性之聚合起始劑。作為油溶性之聚合起始劑,可列舉例如:過氧二碳酸二異丙酯、過氧二碳酸二(2-乙基己)酯、過氧二碳酸二乙氧基乙酯等過碳酸酯化合物;過氧新癸酸三級丁酯、過氧三甲基乙酸三級丁酯、過氧三甲基乙酸三級己酯、過氧新癸酸異丙苯酯等過氧酸酯化合物;過氧化乙醯基環己基碸基、2,4,4-三甲基戊基-2-過氧苯氧乙酸酯、過氧3,5,5-三甲基己醯基、過氧十二醯基等過氧化物;2,2’-偶氮雙(2,4-二甲基戊腈)、2,2’-偶氮雙(異丁腈)、2,2’-偶氮雙(4-甲氧基-2,4-二甲基戊腈)等偶氮化合物等。作為水溶性之聚合起始劑,可列舉例如:過硫酸鉀、過硫酸銨、過氧化氫、氫過氧化異丙苯等。此等聚合起始劑可單獨使用1種,或併用2種以上。In the suspension polymerization of vinyl compounds, oil-soluble or water-soluble polymerization initiators conventionally used in the polymerization of vinyl chloride can be used. Examples of oil-soluble polymerization initiators include percarbonates such as diisopropyl peroxydicarbonate, bis(2-ethylhexyl)peroxydicarbonate, and diethoxyethyl peroxydicarbonate. Compounds; peroxyester compounds such as tertiary butyl peroxyneodecanoate, tertiary butyl peroxytrimethylacetate, tertiary hexyl peroxytrimethylacetate, and cumyl peroxyneodecanoate; Acetyl peroxide, cyclohexyl sulfonyl, 2,4,4-trimethylpentyl-2-peroxyphenoxyacetate, 3,5,5-trimethylhexyl peroxy, peroxydeca Peroxides such as diacetoxy; 2,2'-azobis(2,4-dimethylvaleronitrile), 2,2'-azobis(isobutyronitrile), 2,2'-azobis (4-methoxy-2,4-dimethylvaleronitrile) and other azo compounds. Examples of water-soluble polymerization initiators include potassium persulfate, ammonium persulfate, hydrogen peroxide, and cumene hydroperoxide. These polymerization initiators can be used singly or in combination of two or more.
在乙烯基化合物之懸浮聚合時,聚合溫度並未特別限制,可為20℃左右的低溫度,亦可為大於90℃的高溫度,其中又以20~60℃左右為較佳。又,亦可為了提高聚合反應系統之除熱效率,而使用附有迴流冷凝器之聚合器。In the suspension polymerization of vinyl compounds, the polymerization temperature is not particularly limited. It may be a low temperature of about 20°C or a high temperature of greater than 90°C, and among them, about 20-60°C is preferred. In addition, in order to improve the heat removal efficiency of the polymerization reaction system, a polymerizer with a reflux condenser may be used.
所得之乙烯系樹脂,係可適當摻合塑化劑等而使用於各種成形品用途。The resulting ethylene resin can be suitably blended with a plasticizer and the like to be used in various molded product applications.
在乙烯基化合物之懸浮聚合中,本發明之懸浮聚合用分散穩定劑之使用量(濃度)係相對於乙烯基化合物,而通常為1000ppm以下50ppm以上。若小於50ppm,則有在乙烯基化合物之懸浮聚合時變得易於產生粗粒之可能性。前述ppm意指質量ppm。In the suspension polymerization of a vinyl compound, the usage amount (concentration) of the dispersion stabilizer for suspension polymerization of the present invention is relative to the vinyl compound, and is usually 1000 ppm or less and 50 ppm or more. If it is less than 50 ppm, there is a possibility that coarse particles are likely to be generated during suspension polymerization of the vinyl compound. The aforementioned ppm means mass ppm.
在乙烯基化合物之懸浮聚合時,除了PVA以外,亦可併用將乙烯基化合物在水性溶劑中懸浮聚合時所通常使用之甲基纖維素、羥基乙基纖維素、羥基丙基纖維素、羥基丙基甲基纖維素等水溶性纖維素醚;明膠等水溶性聚合物;山梨醇酐單十二酸酯、山梨醇酐三油酸酯、三硬脂酸甘油酯、環氧乙烷環氧丙烷嵌段共聚物等油溶性乳化劑;聚氧乙烯山梨醇酐單十二酸酯、聚氧乙烯甘油油酸酯、十二酸鈉等水溶性乳化劑等。其添加量並未特別限制,乙烯基化合物每100質量份以0.01質量份以上1.0質量份以下為較佳。In the suspension polymerization of vinyl compounds, in addition to PVA, methyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, and hydroxypropyl cellulose commonly used in suspension polymerization of vinyl compounds in an aqueous solvent can also be used in combination. Water-soluble cellulose ethers such as methyl cellulose; water-soluble polymers such as gelatin; sorbitan monolaurate, sorbitan trioleate, glyceryl tristearate, ethylene oxide and propylene oxide Oil-soluble emulsifiers such as block copolymers; water-soluble emulsifiers such as polyoxyethylene sorbitan monolaurate, polyoxyethylene glycerol oleate, sodium laurate, etc. The addition amount is not particularly limited, and the vinyl compound is preferably 0.01 part by mass or more and 1.0 part by mass or less per 100 parts by mass.
(交聯物) 本發明之PVA之理想的用途為一種交聯物,係該PVA經交聯之交聯物,而將包含前述交聯物之厚度100μm的薄膜浸漬於80℃之熱水1小時之際的溶出率小於10%。(Cross-linked product) The ideal application of the PVA of the present invention is a cross-linked product, which is a cross-linked product of the PVA, and a film with a thickness of 100 μm containing the aforementioned cross-linked product is leached out when immersed in hot water at 80°C for 1 hour The rate is less than 10%.
此處,溶出率可藉由後述的實施例所記載之方法而測定,該溶出率愈小,則可說是耐水性愈優異。又,供測定之薄膜,係可使用含有使用本發明之PVA所製造之交聯物的製膜原液,藉由澆鑄製膜法或熔融擠製製膜法等周知的方法而製造。在本發明中,以將上述薄膜浸漬於80℃之熱水1小時之際的溶出率小於8%為更佳,小於5%為進一步較佳。Here, the elution rate can be measured by the method described in Examples described later, and the smaller the elution rate, the better the water resistance. In addition, the film for measurement can be produced by a well-known method such as a cast film method or a melt extrusion film method using a film forming stock solution containing a cross-linked product manufactured using the PVA of the present invention. In the present invention, the elution rate when the film is immersed in hot water at 80°C for 1 hour is more preferably less than 8%, and more preferably less than 5%.
交聯物之製造方法並未特別限定,但以在酸觸媒之存在下將PVA交聯之製造方法為理想。The manufacturing method of the crosslinked product is not particularly limited, but a manufacturing method of crosslinking PVA in the presence of an acid catalyst is ideal.
(酸觸媒) 酸觸媒之種類並未特別限定,可列舉:磷酸、鹽酸、硫酸等。其中又可理想地使用磷酸。(Acid catalyst) The type of acid catalyst is not particularly limited, and examples thereof include phosphoric acid, hydrochloric acid, and sulfuric acid. Among them, phosphoric acid can be ideally used.
作為酸觸媒之使用方法,並未特別限定。直接使用酸觸媒、或將酸觸媒溶解於溶劑而使用皆無妨。又,在與PVA混合時,在製備PVA水溶液後混合酸觸媒亦無妨,在製備PVA水溶液的同時混合酸觸媒而溶解亦無妨。從抑制副反應的觀點來看,以在製備PVA水溶液後混合酸觸媒之方法為較佳。The method of using the acid catalyst is not particularly limited. It does not matter if the acid catalyst is used directly or the acid catalyst is dissolved in a solvent. In addition, when mixing with PVA, it does not matter if the PVA aqueous solution is prepared and then the acid catalyst is mixed, and the PVA aqueous solution is prepared while mixing the acid catalyst to dissolve it. From the viewpoint of suppressing side reactions, a method of mixing an acid catalyst after preparing the PVA aqueous solution is preferred.
作為酸觸媒之使用量,並未特別限定,但酸觸媒之使用量,係相對於PVA10質量份,而以0.01質量份以上5質量份以下為較佳。當使用量小於0.01質量份時,有無法順利形成交聯物之虞。使用量係以0.05質量份以上為更佳。另一方面,當使用量大於5質量份時,有因PVA之相對濃度降低而無法順利形成交聯物之虞。使用量係以3質量份以下為更佳。The use amount of the acid catalyst is not particularly limited, but the use amount of the acid catalyst is preferably 0.01 parts by mass or more and 5 parts by mass or less with respect to 10 parts by mass of PVA. When the usage amount is less than 0.01 parts by mass, there is a possibility that a cross-linked product cannot be formed smoothly. The usage amount is more preferably 0.05 parts by mass or more. On the other hand, when the amount used is more than 5 parts by mass, the relative concentration of PVA may decrease and the cross-linked product may not be formed smoothly. The usage amount is more preferably 3 parts by mass or less.
在交聯物之製造中,除了上述酸觸媒以外,亦可併用交聯劑。作為交聯劑之例,可列舉:乙二醛、丙二醛、戊二醛等二醛類、乙醛酸鈉、乙醛酸鈣等乙醛酸鹽類、乙二胺、丙二胺、1,3‐雙(胺基甲基)環己烷等二胺類、己二醯肼等二醯肼類。In the production of the cross-linked product, in addition to the above-mentioned acid catalyst, a cross-linking agent may be used in combination. Examples of crosslinking agents include dialdehydes such as glyoxal, malondialdehyde, and glutaraldehyde, glyoxylates such as sodium glyoxylate and calcium glyoxylate, ethylenediamine, propylenediamine, Diamines such as 1,3-bis(aminomethyl)cyclohexane, and dihydrazine such as hexadihydrazine.
上述交聯劑之使用方法並未特別限定,可使用與酸觸媒之使用方法相同的方法。又,上述交聯劑之使用量亦未特別限定,可與酸觸媒之使用量相同。 [實施例]The method of using the above-mentioned crosslinking agent is not particularly limited, and the same method as the method of using the acid catalyst can be used. In addition, the usage amount of the above-mentioned crosslinking agent is not particularly limited, and may be the same as the usage amount of the acid catalyst. [Example]
[PVA之黏度平均聚合度] PVA之黏度平均聚合度係根據JIS K 6726:1994而測定。具體而言,當PVA之皂化度小於99.5莫耳%時,係針對皂化至皂化度成為99.5莫耳%以上之PVA,使用在水中、30℃下測定之極限黏度[η](L/g),藉由下式而求出黏度平均聚合度(P)。 P=([η]×104 /8.29)(1/0.62) [Viscosity average degree of polymerization of PVA] The viscosity average degree of polymerization of PVA is measured in accordance with JIS K 6726:1994. Specifically, when the degree of saponification of PVA is less than 99.5 mol%, the ultimate viscosity [η] (L/g) measured in water at 30°C is used for PVA that is saponified to a degree of saponification of 99.5 mol% or more. , Obtain the viscosity average degree of polymerization (P) by the following formula. P=([η]×10 4 /8.29) (1/0.62)
[PVA之皂化度] PVA之皂化度係根據JIS K 6726:1994而測定。[Saponification degree of PVA] The degree of saponification of PVA is measured in accordance with JIS K 6726:1994.
[PVA之末端醛基之含量] PVA之末端醛基之含量係藉由下述而求出:製備PVA之10質量%水溶液,將5g的該水溶液滴入500g的乙酸甲酯/水=95/5之溶液中並使PVA析出,回收並使其乾燥,將所分離之PVA溶解於DMSO-d6 ,使用400MHz的1 H-NMR而測定。此時,乙烯醇單元之源自次甲基的波峰歸屬於3.2~4.0ppm(積分值P),源自醛基的質子之波峰歸屬於9.5~10ppm附近(積分值Q)。而且,從各波峰藉由下式而求出含量。 醛基之含量(莫耳%)=(Q/P)×100[Content of terminal aldehyde groups of PVA] The content of terminal aldehyde groups of PVA is determined by preparing a 10% by mass aqueous solution of PVA, and dropping 5 g of this aqueous solution into 500 g of methyl acetate/water=95/ PVA was precipitated in the solution of 5, recovered and dried, and the separated PVA was dissolved in DMSO-d 6 and measured using 400 MHz 1 H-NMR. At this time, the peak derived from the methine group of the vinyl alcohol unit is attributable to 3.2 to 4.0 ppm (integrated value P), and the peak derived from the proton of the aldehyde group is attributable to the vicinity of 9.5 to 10 ppm (integrated value Q). Furthermore, the content is obtained from each peak by the following formula. The content of aldehyde group (mol%)=(Q/P)×100
[PVA之紫外線吸收光譜之吸光度] 製作PVA之0.1質量%水溶液。然後,將該水溶液投入光徑長1cm之槽,使用紫外線-可見光光譜儀(島津製作所股份有限公司製UV-2450)而測定280nm之吸光度。[Absorbance of UV absorption spectrum of PVA] A 0.1% by mass aqueous solution of PVA is produced. Then, the aqueous solution was put into a tank with an optical path length of 1 cm, and an ultraviolet-visible spectrometer (UV-2450 manufactured by Shimadzu Corporation) was used to measure the absorbance at 280 nm.
[製造例1 PVA1之製造] 將乙酸乙烯酯(以下有時簡略記載為「VAc」)1500質量份、甲醇10質量份投入聚合槽。其次,在將聚合槽內氮氣取代後將戊二醛12質量份、水12質量份追加投入聚合槽,加熱聚合槽而使升溫至60℃,在作為聚合起始劑之2,2’-偶氮雙(異丁腈)之存在下進行聚合直到聚合率成為25%。一邊添加甲醇一邊進行將減壓下殘存之VAc與甲醇一同趕出系統外之操作,得到聚乙酸乙烯酯(以下有時簡略記載為「PVAc」)之甲醇溶液(濃度40質量%)。其次在甲醇溶劑中,將PVAc中的乙酸乙烯酯單元之濃度稀釋為30質量%,在溫度40℃,以相對於之PVAc為莫耳比0.03之比例使用氫氧化鈉作為皂化觸媒,進行1小時皂化反應。將所得之聚乙烯醇浸漬於乙酸甲酯/甲醇=80/20之清洗液而進行清洗。其次在以離心去除溶劑後進行乾燥,得到PVA1,其黏度平均聚合度為1500,皂化度為99莫耳%,末端醛基之含量為0.1莫耳%,0.1質量%水溶液之280nm的吸光度為0.279。[Manufacturing Example 1" Manufacturing of PVA1] 1500 parts by mass of vinyl acetate (hereinafter sometimes abbreviated as "VAc") and 10 parts by mass of methanol were charged into the polymerization tank. Next, after substituting nitrogen in the polymerization tank, 12 parts by mass of glutaraldehyde and 12 parts by mass of water were added to the polymerization tank, and the polymerization tank was heated to raise the temperature to 60°C. The polymerization is carried out in the presence of nitrobis(isobutyronitrile) until the polymerization rate becomes 25%. While adding methanol, an operation was performed to drive out the VAc remaining under reduced pressure together with methanol from the system to obtain a methanol solution (concentration 40% by mass) of polyvinyl acetate (hereinafter abbreviated as "PVAc"). Secondly, in methanol solvent, dilute the concentration of the vinyl acetate unit in PVAc to 30% by mass, and use sodium hydroxide as the saponification catalyst at a temperature of 40°C at a molar ratio of 0.03 relative to PVAc. Hour saponification reaction. The obtained polyvinyl alcohol was immersed in a cleaning solution of methyl acetate/methanol=80/20 for cleaning. Secondly, after removing the solvent by centrifugation, it was dried to obtain PVA1. Its viscosity average polymerization degree was 1500, saponification degree was 99 mol%, terminal aldehyde group content was 0.1 mol%, and the absorbance at 280nm of 0.1% by mass aqueous solution was 0.279. .
[製造例2~12(PVA2~12之製造)] 除了將乙酸乙烯酯及於聚合時使用的甲醇、水、醛之使用量、醛之種類、聚合反應停止時的聚合率、皂化條件如表1所記載而變更以外,係與製造例1同樣地進行,而製造PVA2~PVA12。將製造條件示於表1,將使用的醛之種類示於表2。[Manufacturing examples 2-12 (manufacturing of PVA2-12)] Except that vinyl acetate and the amount of methanol, water, and aldehyde used in the polymerization, the type of aldehyde, the polymerization rate when the polymerization reaction is stopped, and the saponification conditions are changed as described in Table 1, it is the same as in Production Example 1. Proceed to manufacture PVA2-PVA12. The manufacturing conditions are shown in Table 1, and the type of aldehyde used is shown in Table 2.
[製造例13(PVA13之製造)]
利用與製造例11同樣的方法來製造PVA11,將所得之PVA11以熱風乾燥機在80℃下進行1小時熱處理,製造PVA13。
[表1]
[表2]
實施例1 將PVA(1)10質量份溶解於蒸餾水而作成10質量%水溶液100質量份,添加磷酸0.5質量份作為酸觸媒並混合攪拌,作成樹脂組成物水溶液。將該水溶液澆鑄於聚對苯二甲酸乙二酯(PET)薄膜上,在23℃、50%RH之條件下放置48小時後,在70℃下進行5分鐘加熱處理而得到厚度100μm之薄膜。利用以下的要領來評價所得之薄膜之耐水性時,溶出率為1.5質量%。Example 1 10 parts by mass of PVA (1) was dissolved in distilled water to prepare 100 parts by mass of a 10% by mass aqueous solution, and 0.5 parts by mass of phosphoric acid was added as an acid catalyst and mixed and stirred to prepare an aqueous solution of a resin composition. The aqueous solution was cast on a polyethylene terephthalate (PET) film and left for 48 hours under the conditions of 23° C. and 50% RH, and then heated at 70° C. for 5 minutes to obtain a film with a thickness of 100 μm. When the water resistance of the obtained film was evaluated by the following method, the dissolution rate was 1.5% by mass.
(耐水性) 將所得之薄膜浸漬於80℃的熱水1小時,測定薄膜之溶出率(質量%)。此外,關於溶出率(質量%)之計算,係求出熱水浸漬前的薄膜之乾燥質量X1(g)及熱水浸漬後的薄膜之乾燥質量X2(g),以下式來算出溶出率(質量%)。將結果示於表3。 溶出率(質量%)=[(X1-X2)/X1]×100(Water resistance) The obtained film was immersed in hot water at 80°C for 1 hour, and the elution rate (mass%) of the film was measured. In addition, the calculation of the dissolution rate (mass%) is to obtain the dry mass X1(g) of the film before hot water immersion and the dry mass X2(g) of the film after hot water immersion, and calculate the dissolution rate by the following formula ( quality%). The results are shown in Table 3. Dissolution rate (mass%)=[(X1-X2)/X1]×100
實施例2 除了改變使用之PVA之種類以外,係與實施例1同樣地進行而評價耐水性。將結果示於表3。Example 2 The water resistance was evaluated in the same manner as in Example 1 except that the type of PVA used was changed. The results are shown in Table 3.
比較例1 除了使用PVA6作為PVA以外,係與實施例1同樣地進行而製作薄膜,而試圖進行耐水性之評價。其結果,PVA6因醛基之含量過低而幾乎未顯現耐水性。Comparative example 1 Except for using PVA6 as PVA, a film was produced in the same manner as in Example 1, and an attempt was made to evaluate the water resistance. As a result, PVA6 hardly exhibits water resistance because the content of aldehyde groups is too low.
比較例2 除了使用PVA7作為PVA以外,與實施例1同樣地進行而試圖進行耐水性之評價。其結果,PVA7因黏度平均聚合度過低而幾乎未顯現耐水性。Comparative example 2 Except that PVA7 was used as PVA, it carried out similarly to Example 1, and tried to evaluate the water resistance. As a result, PVA7 hardly exhibited water resistance due to the excessively low viscosity average polymerization.
[表3]
實施例3 將PVA3作為懸浮聚合用分散穩定劑而溶解於去離子水,將PVA3之水溶液100質量份投入殺菌釜。投入之PVA3之量,係相對於氯乙烯(VCM)之投入量為850ppm。其次,添加去離子水,使去離子水之合計成為1200質量份。其次,於殺菌釜添加過氧新癸酸異丙苯酯之70質量%甲苯溶液0.65質量份及過氧新癸酸三級丁酯之70質量%甲苯溶液1.05質量份,於殺菌釜內導入氮氣,使壓力成為0.2MPa。然後將進行氮氣沖洗之操作合計進行5次,將殺菌釜內充分地進行氮氣取代而去除氧氣後,添加氯乙烯940質量份。將殺菌釜內的內容物升溫為57℃而在攪拌下開始氯乙烯之懸浮聚合。聚合開始時之殺菌釜內的壓力為0.80MPa。從聚合開始經過約3.5小時後,在殺菌釜內的壓力成為0.70MPa之時間點停止聚合,去除未反應的氯乙烯,取出聚合反應物,在65℃下進行16小時乾燥,得到氯乙烯聚合物粒子。而且,利用以下所示之方法來評價所得之氯乙烯聚合物粒子。Example 3 PVA3 was dissolved in deionized water as a dispersion stabilizer for suspension polymerization, and 100 parts by mass of the aqueous solution of PVA3 was put into the sterilizer. The input amount of PVA3 is 850ppm relative to the input amount of vinyl chloride (VCM). Next, deionized water is added so that the total amount of deionized water becomes 1200 parts by mass. Next, add 0.65 parts by mass of a 70% by mass toluene solution of cumyl peroxyneodecanoate and 1.05 parts by mass of a 70% by mass toluene solution of tertiary butyl peroxyneodecanoate into the sterilizer, and introduce nitrogen into the sterilizer. , Make the pressure 0.2MPa. Then, the operation of nitrogen flushing was performed 5 times in total, and after the inside of the sterilizer was sufficiently replaced with nitrogen and oxygen was removed, 940 parts by mass of vinyl chloride was added. The content in the sterilizer was heated to 57°C and the suspension polymerization of vinyl chloride was started under stirring. The pressure in the retort at the beginning of the polymerization was 0.80 MPa. After about 3.5 hours from the start of the polymerization, the polymerization was stopped when the pressure in the sterilizer became 0.70 MPa, the unreacted vinyl chloride was removed, and the polymerization reaction product was taken out and dried at 65°C for 16 hours to obtain a vinyl chloride polymer particle. Furthermore, the obtained vinyl chloride polymer particles were evaluated by the method shown below.
(氯乙烯聚合物粒子之評價) 針對所得之氯乙烯聚合物粒子,根據以下的方法而評價(1)平均粒徑、(2)粒度分布及(3)魚眼。將評價結果示於表4。(Evaluation of vinyl chloride polymer particles) With respect to the obtained vinyl chloride polymer particles, (1) average particle size, (2) particle size distribution, and (3) fisheye were evaluated according to the following methods. The evaluation results are shown in Table 4.
(1)平均粒徑 使用泰勒(Tyler)目數基準之篩,藉由JIS Z 8815:1994所記載之乾式篩法而測定粒度分布。將其結果製圖為若生-拉姆拉(Rosin-Rammler)分布式而算出平均粒徑(dp50 )。(1) The average particle size was measured by the dry sieve method described in JIS Z 8815:1994 using a Tyler mesh standard sieve. The result was graphed as Rosin-Rammler distribution, and the average particle diameter (d p50 ) was calculated.
(2)粒度分布 利用下述評價基準來評價未通過篩孔尺寸355μm之篩(JIS標準篩之目數換算為42目數)的氯乙烯聚合物粒子之含量(質量%)。前述含量意指篩上累積(質量%)。又,前述篩之篩孔尺寸係根據JIS Z 8801-1-2006之公稱篩孔尺寸W。 A:小於0.5質量% B:0.5質量%以上小於1質量% C:1質量%以上(2) Particle size distribution The following evaluation criteria were used to evaluate the content (mass %) of vinyl chloride polymer particles that did not pass through a sieve with a mesh size of 355 μm (the JIS standard sieve is converted to 42 meshes). The aforementioned content means accumulation on the sieve (mass %). In addition, the mesh size of the aforementioned sieve is based on the nominal mesh size W of JIS Z 8801-1-2006. A: Less than 0.5% by mass B: 0.5% by mass or more and less than 1% by mass C: 1% by mass or more
利用下述評價基準來評價通過篩孔尺寸355μm之篩且未通過篩孔尺寸250μm之篩(JIS標準之目數換算為60目數)的氯乙烯聚合物粒子之含量(質量%)。前述含量意指篩上累積(質量%)。又,前述篩之篩孔尺寸係根據JIS Z 8801-1-2006之公稱篩孔尺寸W。 A:小於5質量% B:5質量%以上小於10質量% C:10質量%以上The following evaluation criteria were used to evaluate the content (mass%) of vinyl chloride polymer particles that passed through a sieve with a mesh size of 355 μm and did not pass a sieve with a mesh size of 250 μm (the number of meshes in the JIS standard is converted into 60 meshes). The aforementioned content means accumulation on the sieve (mass %). In addition, the mesh size of the aforementioned sieve is based on the nominal mesh size W of JIS Z 8801-1-2006. A: Less than 5 mass% B: 5 mass% or more and less than 10 mass% C: 10% by mass or more
利用下述評價基準來評價通過篩孔尺寸75μm之篩(JIS標準之目數換算為200目數)的氯乙烯聚合物粒子之含量(質量%)。前述含量意指篩上累積(質量%)。又,前述篩之篩孔尺寸係根據JIS Z 8801-1-2006之公稱篩孔尺寸W。 A:小於1質量% B:1質量%以上小於2質量% C:2質量%以上The following evaluation criteria were used to evaluate the content (mass%) of vinyl chloride polymer particles that passed through a sieve with a mesh size of 75 μm (the number of meshes in the JIS standard is 200 meshes). The aforementioned content means accumulation on the sieve (mass %). In addition, the mesh size of the aforementioned sieve is based on the nominal mesh size W of JIS Z 8801-1-2006. A: Less than 1% by mass B: 1% by mass or more and less than 2% by mass C: 2% by mass or more
此外,未通過篩孔尺寸355μm之篩的氯乙烯聚合物粒子之含量及未通過篩孔尺寸250μm之篩的氯乙烯聚合物粒子之含量皆為值愈小則表示粗大粒子愈少而粒度分布愈銳利,聚合穩定性愈優異。又,通過75μm之篩的氯乙烯聚合物粒子之含量少,係表示微粉少且步驟通過性優異。In addition, the content of vinyl chloride polymer particles that have not passed through the sieve with a mesh size of 355 μm and the content of vinyl chloride polymer particles that have not passed through the sieve with a mesh size of 250 μm are both the smaller the value, the smaller the coarse particles and the greater the particle size distribution. Sharp, the better the polymerization stability. In addition, the low content of vinyl chloride polymer particles passing through a 75 μm sieve indicates that there are few fine powders and excellent process passability.
(3)魚眼 將所得之氯乙烯聚合物粒子100質量份、鄰苯二甲酸二辛酯50質量份、三鹼性硫酸鉛5質量份及硬脂酸鋅1質量份在150℃下輥混練7分鐘而製作0.1mm厚的薄片,並且以目視來測定每1000cm2 的魚眼之數。魚眼之數愈少則表示薄片上的缺陷愈少。(3) Fisheye roll knead the obtained vinyl chloride polymer particles 100 parts by mass, dioctyl phthalate 50 parts by mass, 5 parts by mass of tribasic lead sulfate and 1 part by mass of zinc stearate at 150°C A 0.1 mm thick sheet was produced in 7 minutes, and the number of fish eyes per 1000 cm 2 was measured visually. The smaller the number of fisheyes, the fewer defects on the flakes.
實施例4~5 除了分別使用PVA4~5來取代PVA3以外,係與實施例3同樣地進行氯乙烯之懸浮聚合。將所得之氯乙烯聚合物粒子之評價結果示於表4。當使用本發明之PVA作為懸浮聚合用分散穩定劑時,所得之氯乙烯聚合物粒徑不會變得粗大,顯示良好的聚合穩定性,且微粉少,魚眼數少。Examples 4~5 The suspension polymerization of vinyl chloride was carried out in the same manner as in Example 3 except that PVA4 to 5 were used instead of PVA3, respectively. Table 4 shows the evaluation results of the obtained vinyl chloride polymer particles. When the PVA of the present invention is used as a dispersion stabilizer for suspension polymerization, the obtained vinyl chloride polymer does not become coarser, exhibits good polymerization stability, and has less fine powder and fewer fish eyes.
比較例3 除了使用PVA8作為PVA以外,係與實施例3同樣地進行氯乙烯之懸浮聚合。將所得之氯乙烯聚合物粒子之評價結果示於表4。PVA8由於醛基之含量多,因此成為所得之氯乙烯聚合物粒子之平均粒徑大,粗大粒子、微粉之比例多,魚眼亦多之結果。Comparative example 3 The suspension polymerization of vinyl chloride was carried out in the same manner as in Example 3 except that PVA8 was used as the PVA. Table 4 shows the evaluation results of the obtained vinyl chloride polymer particles. Due to the high content of aldehyde groups in PVA8, the resulting vinyl chloride polymer particles have a large average particle size, a large proportion of coarse particles and fine powders, and a large number of fish eyes.
比較例4 除了使用PVA9作為PVA以外,係與實施例3同樣地進行氯乙烯之懸浮聚合。將所得之氯乙烯聚合物粒子之評價結果示於表4。PVA9由於皂化度過低,因此成為所得之氯乙烯聚合物粒子之平均粒徑大,粗大粒子、微粉之比例多,魚眼亦多之結果。Comparative example 4 The suspension polymerization of vinyl chloride was carried out in the same manner as in Example 3 except that PVA9 was used as the PVA. Table 4 shows the evaluation results of the obtained vinyl chloride polymer particles. PVA9 is too low in saponification, so the average particle size of the obtained vinyl chloride polymer particles is large, the ratio of coarse particles and fine powder is large, and the result is that there are also many fish eyes.
比較例5 除了使用PVA10作為PVA以外,係與實施例3同樣地進行氯乙烯之懸浮聚合。將所得之氯乙烯聚合物粒子之評價結果示於表4。PVA10由於黏度平均聚合度過高,因此成為所得之氯乙烯聚合物粒子之平均粒徑大,粗大粒子、微粉之比例多,魚眼亦多之結果。Comparative example 5 The suspension polymerization of vinyl chloride was carried out in the same manner as in Example 3 except that PVA10 was used as the PVA. Table 4 shows the evaluation results of the obtained vinyl chloride polymer particles. The average viscosity of PVA10 is too high, so the resultant vinyl chloride polymer particles have a large average particle size, a large proportion of coarse particles and fine powders, and a large number of fish eyes.
比較例6 除了使用PVA11作為PVA以外,係與實施例3同樣地進行氯乙烯之懸浮聚合。將所得之氯乙烯聚合物粒子之評價結果示於表4。PVA11由於醛基之含量過少,因此成為所得之氯乙烯聚合物粒子之平均粒徑大,粗大粒子、微粉之比例多,魚眼亦多之結果。Comparative example 6 The suspension polymerization of vinyl chloride was carried out in the same manner as in Example 3 except that PVA11 was used as the PVA. Table 4 shows the evaluation results of the obtained vinyl chloride polymer particles. The content of aldehyde groups in PVA11 is too small, so the resultant vinyl chloride polymer particles have a large average particle size, a large proportion of coarse particles and fine powders, and a large number of fish eyes.
比較例7 除了使用PVA12作為PVA以外,係與實施例3同樣地進行氯乙烯之懸浮聚合。將所得之氯乙烯聚合物粒子之評價結果示於表4。PVA12由於是源自在單醛之存在下聚合乙酸乙烯酯而得之聚乙酸乙烯酯的PVA,且於PVA之末端不具有醛基,因此成為所得之氯乙烯聚合物粒子之平均粒徑大,粗大粒子、微粉之比例多,魚眼亦多之結果。Comparative example 7 The suspension polymerization of vinyl chloride was carried out in the same manner as in Example 3 except that PVA12 was used as PVA. Table 4 shows the evaluation results of the obtained vinyl chloride polymer particles. Since PVA12 is a PVA derived from polyvinyl acetate obtained by polymerizing vinyl acetate in the presence of a single aldehyde, and does not have an aldehyde group at the end of the PVA, the resulting vinyl chloride polymer particles have a large average particle size. The result is that the proportion of coarse particles and fine powder is large, and there are also many fish eyes.
比較例8
除了使用PVA13作為PVA以外,係與實施例3同樣地進行氯乙烯之懸浮聚合。將所得之氯乙烯聚合物粒子之評價結果示於表4。PVA13雖然吸光度之值高,但醛基之含量過少,因此成為所得之氯乙烯聚合物粒子之平均粒徑大,粗大粒子、微粉之比例多,魚眼亦多之結果。
[表4]
如實施例所示,本發明之PVA可使用酸等而簡便地形成交聯物,此時的耐水性優異。又,若將本發明之PVA使用於乙烯基化合物之懸浮聚合用分散穩定劑則聚合穩定性優異,且所得之氯乙烯聚合物粒子(乙烯系聚合物)係平均粒徑小,粗大粒子、微粉之生成亦少,可減少魚眼。所以乙烯系聚合物之生產性、加工性優異。因此,本發明之工業上的有用性極高。As shown in the examples, the PVA of the present invention can easily form a crosslinked product by using an acid or the like, and the water resistance in this case is excellent. In addition, if the PVA of the present invention is used as a dispersion stabilizer for suspension polymerization of vinyl compounds, the polymerization stability is excellent, and the obtained vinyl chloride polymer particles (vinyl polymers) have small average particle diameters, coarse particles, and fine powders. The formation is also less, which can reduce fish eyes. Therefore, the ethylene polymer is excellent in productivity and processability. Therefore, the industrial usefulness of the present invention is extremely high.
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