1,2,3,4-シクロブタンテトラカルボン酸二無水物

説明Cyclobutane-1,2,3,4-tetracarboxylic dianhydride (CBDA) is an anhydride with a cis-trans-cis configuration. It can be used to synthesise polyimide films. Polymer films have excellent heat resistance, are transparent and colourless, with transmittance ranging from 81.5% to 85.8%, and are suitable for use in high quality display materials such as liquid crystal displays. The polymers made with pyrrolidine dianhydride instead of CBDA are dark yellow in colour and have a lower transmittance in the range of 48% to 63.9%.

使用1,2,3,4-Cyclobutanetetracarboxylic Dianhydride and diamine monomer are used for preparation a polyimide (PI), the type of polyimide has excellent electrical characteristics and optical type, with the material prepared the PI film, in addition to having a higher rate cast visible outside, and can withstand high temperatures thirty-four Baidu. Its performance is very good, is the preparation of a liquid crystal display with an ideal material for the film.

用途1,2,3,4-シクロブタンテトラカルボン酸二無水物（CBDA）は、透明ポリイミド（PI）薄膜を合成するための重要なモノマーの一つである。CBDAと芳香族ジアミンを用いて製造されたポリイミド樹脂は、透明かつ無色であり、優れた溶解性、耐熱性、および光学透明性を有することが報告されている。さらに、側鎖にフッ素基を有するジカルボン酸無水物およびジアミンモノマーを用いて、透明および淡色のポリイミドが調製されている。これらのPIフィルムは可視光領域（400–700 nm）において良好な光学透明度を示し、450 nmにおける透過率は80%を超えており、光学波長帯域において吸収はほとんど見られない[1]。

製造方法Preparation of 1,2,3,4- cyclobutanetetracarboxylic acid dianhydride (CBDA)To a 2L quartz glass photoreactor equipped with sixteen UV lamps (300nm) , a stirrer and a cooler were attached and 250ml of ethyl acetate and 100g of maleic anhydride were added thereto followed by stirring for complete mixing. To avoid an excessive temperature increase, an air-cooling type cooler was first run and then UV light was illuminated for a photoreaction for 24h with stirring so as not to have the reactants adhered to the reactor walls. As a result, 71g of white solid was obtained. After the filtration, the white solid was dried for 24h in a vacuum dryer at 60°C Thus-obtained solid was then added to acetic anhydride, dissolved therein and slowly heated to 150°C followed by the reaction for 24h . Hot reaction solution was filtered through a filter paper to remove impurities and kept in a freezer at the temperature of 0°C or less for recrystallization for 24h to obtain a yellow solid. Thus-obtained solid was filtered and washed three times with 1,4-dioxane to remove acetic anhydride, and then dried in a vacuum oven at 60°C for 48h to obtain 64g of 1, 2, 3, 4 -cyclobutane tetracarboxylic acid dianhydride (CBDA) .

合成方法1,2,3,4-シクロブタンテトラカルボン酸二無水物（CBDA）は、UV照射下におけるテイラーフロー内のキャピラリーマイクロリアクターにおいて、無水マレイン酸の光二量化反応により合成された。この光化学反応プロセスには、CBDAの堆積による流路の閉塞を防ぐため、不活性ガスと超音波の両方が導入された。水銀ランプの出力が高いほど、反応物濃度が低いほど、滞留時間が長いほど、またキャピラリーの内径が小さいほど、CBDAの収率が高くなることが判明した。内径0.5 mmのキャピラリーマイクロリアクターにおいて、実質滞留時間30分の場合、CBDAの収率は最大66.3%に達した[2].