MISCIBILITY AND THERMAL DEGRADATION KINETICS OF POLY-β-ALANINE/POLY(3-HYDROXYPROPIONATE) BLENDS

Abstract

Poly-β-alanine (PBA) and poly(3-hydroxypropionate) (PHP) were synthesized via base-catalyzed hydrogen transfer polymerization (HTP) of acrylamide and acrylic acid, respectively. Blends of PBA/PHP with different composition (PHP content, 5% to 75%) were studied using FTIR, DSC, TGA, XRD and polarized optical microscope to reveal both miscibility and thermal degradation kinetics of PBA/PHP blends. Optical images of blends were transparent and entirely uniform. Characteristic FTIR bands of both components shifted in higher frequencies with increasing fraction of another component. Melting temperature (Tm), thermal decomposition temperatures (Td), and enthalpy of fusion (ΔHf) of PHP decreased with increasing PBA fraction in blends. Thermal degradation kinetics of both components were studied by Freeman-Carroll method. Activation energies of thermal degradations of blend components were determined with good regression coefficients (at least 0.994). Activation energies of decomposition decreased from 224.14 to 86.125 kJmol -1 with increasing PHP content. XRD spectra of blends exhibited lower peak intensities than those of neat polymers. The spectroscopic, thermal, and optical methods revealed that PBA and PHP were miscible with a good compatibility in amorphous phase.

Poly(3-hydroxypropionate): Biosynthesis Pathways and Malonyl-CoA Biosensor Material Properties

“…Poly(3HP) possess a melting peak temperature of 79.1 o C in its pure state and about 77.7 o C in blends with the Poly(3HP) content ranging from 50–90%, a glass transition temperature of −20, and a fusion enthalpy value of 64J/g, as shown in Table 1 ( Andreeßen et al, 2014b ). Although poly(3HP) has received focus to be environmentally degradable material, it has some limitations due to brittleness (high crystallinity), limited processability, and high hydrophobicity ( Catiker and Basan, 2017 ). Some studies have been conducted on poly(3HP) blends to eliminate these abnormalities ( He et al, 2000 ).…”

“…Polymer blends and polymer thermal degradation of poly (3-HP) have been investigated by applying one or more of the following techniques such as thermogravimetry (TGA), differential thermal analysis (DTA), dynamic mechanical, thermal analysis (DMTA), differential scanning calorimetry (DSC), and nuclear magnetic resonance (NMR) ( Catiker and Basan, 2017 ). The miscibility and thermal degradation of [poly(3HP)] and poly-β-alanine (poly (BA) have been studied thoroughly.…”

“…The miscibility and thermal degradation of [poly(3HP)] and poly-β-alanine (poly (BA) have been studied thoroughly. Catiker and Basan (2017) studied the miscibility of poly(3HP) and poly(BA) and found out that blends of these two components are miscible in the amorphous phase. The miscibility occurred because of the suppression of the crystallinity of both elements in the blends.…”

“…The miscibility occurred because of the suppression of the crystallinity of both elements in the blends. The thermal degradation of poly(3HP) and poly(BA) was examined, and the results have shown that combinations of these components turned to decompose thermally via fast and single-step degradation ( Catiker and Basan, 2017 ).…”

Synthesis and characterization of comb-type graft copolymers by redox polymerization and "click" chemistry method

“…4. As reported for many copolymers [38][39][40][41], moieties in a copolymer exhibit decomposition curves as if they are alone. TGA has showed interesting properties of the copolymers indicating continuous weight loss starting from 180 °C to nearly 510 °C with derivatives at 232 °C and 417 °C through two steps (Fig.…”