Tarvainen Maarit, Sutinen Riitta, Peltonen Soili, Mikkonen Hannu, Maunus Jaana, Vähä-Heikkilä Kalle, Lehto Vesa-Pekka, Paronen Petteri
Department of Pharmaceutics, University of Kuopio, P.O. Box 1627, FIN-70211, Kuopio, Finland.
Eur J Pharm Sci. 2003 Aug;19(5):363-71. doi: 10.1016/s0928-0987(03)00137-4.
The aim of this study was to investigate the ability of n-alkenyl succinic anhydrides (n-ASAs) to improve the film-forming characteristics of a novel coating polymer, potato starch acetate degree of substitution 2.8 (SA). n-ASAs were also applied to improve the otherwise brittle properties of ethyl cellulose (EC) aqueous dispersion (Aquacoat) and EC solvent-based films.
The effectiveness of two n-ASAs, 2-octenyl succinic anhydride (OSA) and 2-dodecen-1-ylsuccinic anhydride were evaluated as plasticizers. Mechanical properties, both water vapor and drug permeabilities, and glass transition temperatures of the cast free films were measured. Triethyl citrate and dibutyl sebacate were used as reference plasticizers.
The long hydrocarbon chain of n-ASA, with its accessible carbonyl groups, enabled a strong plasticization effect on the tested polymers. Due to the excellent mechanical properties (i.e., a tough film structure with considerable flexibility) and low permeability of the plasticized films, n-ASAs, and especially OSA proved to be an ideal plasticizer particularly for EC based coatings. Also, the EC aqueous dispersion plasticized with n-ASAs resulted in a markedly enhanced coalescence of the colloidal polymer particles, even at low drying temperatures.
In applications where a coating with high flexibility is required, n-ASAs can be used as plasticizers at moderately high concentrations (up to 60-70%, w/w) without losing the high tensile strength, excellent toughness and low permeability of EC and SA films.
本研究旨在探究正链烯基琥珀酸酐（n-ASA）改善新型包衣聚合物——取代度为2.8的醋酸马铃薯淀粉（SA）成膜特性的能力。n-ASA还被用于改善乙基纤维素（EC）水分散体（Aquacoat）和EC溶剂型薄膜原本易碎的性质。
评估了两种n-ASA，即2-辛烯基琥珀酸酐（OSA）和2-十二碳烯基琥珀酸酐作为增塑剂的效果。测量了流延游离膜的机械性能、水蒸气和药物渗透率以及玻璃化转变温度。柠檬酸三乙酯和癸二酸二丁酯用作参比增塑剂。
n-ASA的长烃链及其可及的羰基对受试聚合物产生了强烈的增塑作用。由于增塑膜具有优异的机械性能（即具有相当柔韧性的坚韧膜结构）和低渗透性，n-ASA，尤其是OSA被证明是一种理想的增塑剂，特别是对于基于EC的包衣。此外，用n-ASA增塑的EC水分散体即使在低干燥温度下也能显著增强胶体聚合物颗粒的聚结。
在需要高柔韧性包衣的应用中，n-ASA可以在中等至高浓度（高达60-70%，w/w）下用作增塑剂，而不会丧失EC和SA薄膜的高拉伸强度、优异韧性和低渗透性。
