1. Synthesis and characterization of chitosan-g-poly(acrylic acid)/attapulgite superabsorbent composites Junping Zhang a,b, Qin Wang a,b, Aiqin Wang a,* Carbohydrate Polymers 68 (2007) 367–374 指導教授：林鴻儒 博士 姓名：徐楓茜 日期： 98.08.14

2. Outline Introduction Materials Experimental Results and discussion Conclusions

3. Introduction 親水性的網狀高分子，可把水份鎖在裡面，不易流失。像 傳統的吸水性材料如海綿，棉和紙漿等。這些高吸水性材 料廣泛的應用在衛生產品，園藝，藥物釋放，煤炭脫水， 然而這些材料都容易降解，對環境有影響。 因此 Kiatkamjornwong 等人利用親水性單體乙烯基接枝在天 然高分子澱粉及 Chitosan 側鏈上的 -NH 2 及 -OH ，使其水膠 具有吸水之性質。 現今 Chitosan 廣泛的應用於生醫材料，且具有較好的生物 相容性。 因此利用高吸水性材料丙烯酸接枝 Chitosan ，不僅可以改 善生物降解的問題，且材料也具有吸水的特點。

4. 近年來， Clay 常應用於與吸水性材料做結合，來改善其膨 潤性質與降低成本並可加強水膠之強度。 Introduction

5. Material Acrylic acid (AA) ammonium persulfate (APS) N,N’-methylenebisacrylamide (MBA) Chitosan (CTS) Attapulgite (APT)

6. Experimental - different MW 40 ml distilled water 2 g CTS 30% H 2 O 2 (0.3, 1.0, 3.7, 9.4ml) Suspension Stirred and kept at 50 ℃, 2h Filtrated Solid Solid (washed) Washed with distilled water to pH=7 Solid Dried under vacuum at 50 ℃ Average molecular weight of CTS was determined by viscometry measurement

7. Preparation of CTS-g-PAA/APT 1% acetic acid solution 30ml In the 250 ml four-neck flask, equipped with a mechanical stirrer, a reflux condenser, a funnel and a nitrogen line Purged with nitrogen for 30 min to remove oxygen and heated to 60 ℃ 0.10 g APS 3.55 g AA MBA and APT 10 min The water bath, kept 60 ℃, 3h Transferred 1M NaOH aqueous solution to be neutralized to pH=7, dried in oven or dewatering agents, methanol, ethanol and acetone Use filter paper wiping off excessive dewatering agents Spread on a dish to dry overnight at room temperature Use 40-80 mesh milled CTS

8. Results and discussion Fig. 2. IR spectra of (a) APT, (b) uncrosslinked CTS-g-PAA/APT, (c) CTS, (d) CTS-g-PAA and (e) CTS-g-PAA/APT. Weight ratio of AA to CTS is 7.2; average molecular weight of CTS is 22.9*10 4 ; MBA content is 2.94 wt%; APT content is 10 wt%; dewatered with methanol. OH C-H COOHCOO - C-H C=O -NHCO C 3 -OH C 6 -OH Si-OH COO - -NH 2 COO - C-H

9. Fig. 3. TGA curves of CTS-g-PAA and CTS-g-PAA/APT. Weight ratio of AA to CTS is 7.2; average molecular weight of CTS is 22.9*10 4 ; MBA content is 2.94 wt%; APT content is 10 wt%; dewatered with methanol. 381.7 ℃ 578.4 ℃ 604.3 ℃

10. Fig. 4. SEM micrographs of (a) APT, (b) CTS-g-PAA and (c) CTS-g-PAA/APT superabsorbent composite. Weight ratio of AA to CTS is 7.2; average molecular weight of CTS is 22.9*10 4 ; MBA content is 2.94 wt%; APT content is 10 wt%; dewatered with methanol.

11. Fig. 6. Variation of water absorbency for the CTS-g-PAA/APT superabsorbent composite with MBA content. Weight ratio of AA to CTS is 7.2; average molecular weight of CTS is 22.9*10 4 ; APT content is 10 wt%; dewatered with methanol. Fig. 5. Variation of water absorbency for the CTS-g-PAA/APT superabsorbent with average molecular weight of CTS. Weight ratio of AA to CTS is 7.2; MBA content is 2.94 wt%; APT content is 10 wt%; dewatered with methanol.

12. Fig. 7. Variation of water absorbency for the CTS-g-PAA/APT superabsorbent composite with weight ratio of AA to CTS. Average molecular weight of CTS is 22.9*10 4 ; MBA content is 2.94 wt%; APT content is 10 wt%; dewatered with methanol. Fig. 8. Variation of water absorbency for the CTS-g-PAA/APT superabsorbent composite with weight ratio of AA to CTS. Weight ratio of AA to CTS is 7.2; average molecular weight of CTS is 22.9*10 4 ; MBA content is 2.94 wt%; dewatered with methanol.

13. Fig. 9. Variation of water absorbency for the CTS-g-PAA/APT superabsorbent composite with dewatering agents. Weight ratio of AA to CTS is 7.2; average molecular weight of CTS is 22.9 *10 4 ; MBA content is 2.94 wt%; APT content is 30 wt%.

14. Conclusion CTS, AA and APT 接枝聚合後，使用 NaOH 中和，可得到新穎的超吸水複合材料。 CTS 的 -OH, -NH 2, -NHCO 和 APT 的 -OH 會與 AA 接枝聚合成水膠。 以 TGA 和 SEM 觀察其材料可看出，添加 APT 後，可以增加材料的熱穩定性及其網狀 結構的孔洞會更加緊實。 少量的 APT 可改善 CTS-g-PAA 的吸水性。