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62 KKU Science Journal Volume 39 Number 1 <strong>Review</strong><br />

(a)<br />

Sn(Oct) 2<br />

+ R-OH<br />

OctSn-OR + OctH<br />

Stannous octoate Hydroxy compound Stannous alkoxide<br />

O<br />

(b)<br />

OctSn-OR<br />

+<br />

n<br />

O<br />

O<br />

ROP<br />

OctSn<br />

O<br />

O-CH-C<br />

CH 3<br />

OR<br />

2n<br />

Stannous alkoxide<br />

O<br />

Lactide<br />

Poly(lactide)<br />

√Ÿª∑’Ë 13 ªØ‘°‘√‘¬“æÕ≈‘‡¡Õ‰√‡´—π·∫∫‡ªî¥«ß¢Õß·≈§‰∑¥å‚¥¬„â ·µππ— ÕÕ°‚∑‡Õ∑·≈– “√ª√–°Õ∫‰Œ¥√Õ°´‘≈<br />

‡ªìπ√–∫∫‡√‘Ë¡ªØ‘°‘√‘¬“ ‚¥¬°“√‡°‘¥ ·µππ— Õ—≈§Õ°‰´¥å (a) ¢—ÈπµÕπ°“√‡°‘¥ ·µππ— Õ—≈§Õ°‰´¥å ·≈–<br />

(b) ¢—ÈπµÕπ°“√‡ªî¥«ß·À«π¢Õß·≈§‰∑¥å (∑’Ë¡“: Dechy-Cabaret et al., 2004)<br />

¡∫—µ‘∑“ߧ«“¡√âÕπ¢ÕßæÕ≈‘·≈§µ‘°·Õ´‘¥<br />

”À√—∫ PLLA ·≈– PDLA ‡ªìπæÕ≈‘‡¡Õ√å<br />

°÷Ëߺ≈÷° (semi-crystalline polymers) ∑’Ë¡’§à“Õÿ≥À¿Ÿ¡‘<br />

°“√À≈Õ¡ (melting temperatures, T m<br />

) Õ¬Ÿà„πà«ß<br />

ª√–¡“≥ 170-180 Õß»“‡´≈‡´’¬ ·≈–¡’§à“Õÿ≥À¿Ÿ¡‘°“√<br />

‡ª≈’ˬπ ∂“π–§≈⓬·°â« (glass-transition temperature,<br />

T g<br />

) Õ¬Ÿà„πà«ßª√–¡“≥ 60 - 65 Õß»“‡´≈‡´’¬ ¢≥–∑’Ë<br />

PDLLA ‡ªìπæÕ≈‘‡¡Õ√åÕ —≥∞“π (amorphous<br />

polymer) ‰¡à¡’§«“¡‡ªìπº≈÷° ®÷߉¡àª√“°Ø§à“ T m<br />

‚¥¬<br />

¡’§à“ T g<br />

Õ¬Ÿà„πà«ßª√–¡“≥ 50-60 Õß»“‡´≈‡´’¬<br />

(Maharana et al., 2009) ‚¥¬§à“ T g<br />

·≈– T m<br />

¢Õß<br />

æÕ≈‘·≈§µ‘°·Õ´‘¥®–¡’§à“¡“°¢÷Èπ ‡¡◊ËÕ§«“¡¬“«¢Õß<br />

‚¡‡≈°ÿ≈ À√◊ÕπÈ”Àπ—°‚¡‡≈°ÿ≈¢ÕßæÕ≈‘·≈§µ‘°·Õ´‘¥<br />

‡æ‘Ë¡¢÷Èπ<br />

¡∫—µ‘°“√≈–≈“¬¢ÕßæÕ≈‘·≈§µ‘°·Õ´‘¥<br />

§«“¡ “¡“√∂„π°“√≈–≈“¬ (solubility) „π<br />

µ—«∑”≈–≈“¬Õ‘π∑√’¬å¢Õß PLLA ·≈– PDLLA · ¥ß<br />

„πµ“√“ß∑’Ë 1 ‚¥¬ PDLA ®–¡’§«“¡ “¡“√∂„π°“√<br />

≈–≈“¬‡àπ‡¥’¬«°—π°—∫ PLLA ®“°µ“√“ß∑’Ë 1 æ∫«à“<br />

PDLLA “¡“√∂≈–≈“¬„πµ—«∑”≈–≈“¬Õ‘π∑√’¬å‰¥â<br />

À≈“¬π‘¥¡“°°«à“ PLLA ‡π◊ËÕß®“°§«“¡‡ªìπº≈÷°¢Õß<br />

PLLA ∑”„Àâ “¡“√∂≈–≈“¬„πµ—«∑”≈–≈“¬Õ‘π∑√’¬å<br />

µà“ßʉ¥âπâÕ¬°«à“ PDLLA

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