［実施例１］
容量が２０リットルで、バッフルおよびファウドラ型撹拌翼を備えたステンレス製オートクレーブに、メタクリル酸メチル／アクリルアミド共重合体系懸濁剤（以下の方法で調整した。メタクリル酸メチル２０重量部、アクリルアミド８０重量部、過硫酸カリウム０．３重量部、イオン交換水１５００重量部を反応器中に仕込み反応器中を窒素ガスで置換しながら７０℃に保つ。反応は単量体が完全に、重合体に転化するまで続け、メタクリル酸メチルとアクリルアミド共重合体の水溶液として得る。得られた水溶液を懸濁剤として使用した。）０．０５部をイオン交換水１６５部に溶解した溶液を供給し、４００ｒｐｍで撹拌し、系内を窒素ガスで置換した。次に、下記混合物質を反応系を撹拌しながら添加し、７０℃に昇温した。内温が７０℃に達した時点を重合開始として、１８０分間保ち、重合を終了した。以降、通常の方法に従い、反応系の冷却、ポリマーの分離、洗浄、乾燥を行い、ビーズ状の共重合体（Ａ−１）を得た。この共重合体（Ａ−１）の重合率は９８重量％であった。
メタクリル酸（ＭＡＡ） ２７重量部
メタクリル酸メチル（ＭＭＡ） ７３重量部
ｔ−ドデシルメルカプタン ０．８重量部
２，２’−アゾビスイソブチロニトリル ０．４重量部
このビーズ状共重合体（Ａ−１）を、スクリュウ径３０ｍｍ、Ｌ／Ｄが２５のベント付き同方向回転２軸押出機（池貝鉄工製 ＰＣＭ−３０）のホッパー口より供給して、樹脂温度２８０℃、スクリュウ回転数１５０ｒｐｍで溶融押出し、ペレット状のグルタル酸無水物単位を含有する熱可塑性重合体（Ｂ−１）を得た。得られた熱可塑性重合体（Ｂ−１）を赤外分光光度計を用いて分析した結果、１８００ｃｍ−１及び１７６０ｃｍ−１に吸収ピークが確認され、この共重合体（Ａ−１）中にグルタル酸無水物単位が形成していることを確認した。また、この共重合体を重ジメチルスルホキシドに溶解させ、室温（２３℃）にて１Ｈ−ＮＭＲを測定し、共重合体組成を決定したところ、メタクリル酸メチル（ＭＭＡ）単位７５重量％、グルタル酸無水物単位２０重量％、メタクリル酸（ＭＡＡ）単位５重量％であった。また、この熱可塑性重合体（Ｂ−１）の極限粘度は０．４６ｄｌ／ｇであった。得られた熱可塑性重合体（Ｂ−１）を、射出成形機（東芝機械社製、ＩＳ５５ＥＰＮ）に供し、シリンダー温度２８０℃、金型温度８０℃で、それぞれの試験片を成形し、評価した。各種物性測定結果を表１に示した。
[Example 1]
In a stainless steel autoclave having a capacity of 20 liters and having a baffle and a Faudra type stirring blade, a methyl methacrylate / acrylamide copolymer suspension (prepared by the following method: 20 parts by weight of methyl methacrylate, 80 parts by weight of acrylamide) , 0.3 parts by weight of potassium persulfate and 1500 parts by weight of ion-exchanged water were charged into a reactor, and the temperature of the reactor was maintained at 70 ° C. while replacing the reactor with nitrogen gas. To obtain an aqueous solution of methyl methacrylate and acrylamide copolymer. The obtained aqueous solution was used as a suspending agent.) A solution in which 0.05 part was dissolved in 165 parts of ion-exchanged water was supplied, and the solution was supplied at 400 rpm. After stirring, the inside of the system was replaced with nitrogen gas. Next, the following mixture was added while stirring the reaction system, and the temperature was raised to 70 ° C. The time when the internal temperature reached 70 ° C. was defined as the start of polymerization, and was maintained for 180 minutes to complete the polymerization. Thereafter, the reaction system was cooled, the polymer was separated, washed, and dried according to a usual method, to obtain a beaded copolymer (A-1). The polymerization rate of this copolymer (A-1) was 98% by weight.
27 parts by weight of methacrylic acid (MAA) 73 parts by weight of methyl methacrylate (MMA) 0.8 part by weight of t-dodecyl mercaptan 0.4 part by weight of 2,2'-azobisisobutyronitrile 0.4 part by weight of this bead-like copolymer (A -1) is supplied from a hopper port of a co-rotating twin-screw extruder (PCM-30 manufactured by Ikegai Iron Works) with a screw diameter of 30 mm and an L / D of 25 at a resin temperature of 280 ° C. and a screw rotation speed of 150 rpm. The resin was melt-extruded to obtain a thermoplastic polymer (B-1) containing pelletized glutaric anhydride units. As a result of analyzing the obtained thermoplastic polymer (B-1) using an infrared spectrophotometer, absorption peaks were confirmed at 1800 cm-1 and 1760 cm-1. It was confirmed that glutaric anhydride units were formed. Further, this copolymer was dissolved in heavy dimethyl sulfoxide, and 1H-NMR was measured at room temperature (23 ° C.) to determine the copolymer composition. As a result, 75% by weight of methyl methacrylate (MMA) unit was obtained, and glutaric acid was obtained. The amount of anhydride units was 20% by weight and the amount of methacrylic acid (MAA) units was 5% by weight. The intrinsic viscosity of the thermoplastic polymer (B-1) was 0.46 dl / g. The obtained thermoplastic polymer (B-1) was subjected to an injection molding machine (manufactured by Toshiba Machine Co., Ltd., IS55EPN), and each test piece was molded at a cylinder temperature of 280 ° C. and a mold temperature of 80 ° C., and evaluated. . Table 1 shows the measurement results of various physical properties.