CHAPTER 1
 INTRODUCTION

 The potential applications of biologically related polymers are an ever-growing

area of interest in polymer chemistry. The interest in incorporating amino acids into

polymers began with Pino in the 1960's.1 Poly (ester amide) polymers (PEA)s are

thermoplastics with a broad range of useful applications. PEAs are currently being

investigated as biodegradable thermoplastic polymers. The architecture of the PEA

polymers is a blend of polyamide and polyester polymer character. This leads to a blend

of the characteristic behavior and properties of these two distinct polymers as well. The

thermal properties of PEAs include higher melt transitions and increased thermal stability

versus polyesters. Conversely, the characteristic thermal properties are lower for PEAs

than for polyamides. Polyamides tend to be high melting and thermally stable. These

characteristics make polyamides difficult to process. PEAs represent a mixture of

polyester and polyamide character and therefore the corresponding thermal properties are

a blend of the two homopolymers. The lower melt transitions versus polyamides mean

that molding, shaping and extruding are all possible.

 The biological degradation behavior for PEAs is generally less complete than for

polyesters but much more complete than polyamides. This is due to the ester bond being

more readily hydrolyzed than the corresponding amide bond. As a result, it is

preferentially cleaved by enzymes.2 In PEAs, the combination of the bonding from two

parent polymer families can be used to tailor the final thermal and enzymatic properties

of the synthesized poly (ester amide) polymer.3 The blend of characteristics is