Effects of Surrounding Media

Of the parameters of the surrounding media shown in Table 8.3, pH and temperature are discussed here. 

The hydrolytic degradation temperature (Th) can be divided into three ranges (1)  

TABLE 21.5 Equilibrium Melting Temperature (7 ) and Folding Surface Free Energy (Oe) for PLLA Having Different Folding Snrfac Structures [62, 67, 272, 276-287] 

PLLA Specimens Structures of Folding Surface (K) (K) (K) (erge/cm ) (erg/cm ) 

Crystalline residues Very short chains with a free  

Hydrolyzed at 97°C [62] Crystallized films Folding chains, tie chains. 464.5 56.4 38.8 

Single crystals Folding chains, a trace amount  

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