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Poly (propylene carbonate) (PPC) is by the synthesis of alternating copolymers of carbon dioxide (CO2) and propylene oxide (PO). PPC compared with other polyesters, low prices, and detection by the State Environmental Protection Agency, can be completely degraded, and can be widely used in disposable packaging materials as well as medical and other fields. PPC has a glass transition temperature (Tg) is low, the soft material, so that the presence of the terminal hydroxyl PPC prone Solutions zipper \Therefore, the physical or chemical modification of the PPC, has greater practical significance to improve the mechanical properties and thermal properties. To start the paper work from the enhanced functionality and workability of the PPC. First, by introducing a nucleating agent (TMC-328) to the performance improvement of the crystallinity of the polylactic acid (PLA), the PLA crystallization modified process parameters, and thus make the PPC, PLA, and TMC-328 melt blending comprehensive performance good blend; second, in two system PPC / PLA, prepared by introducing a polycaprolactone (PCL) combined properties good ASP melt blend; Third, by introducing maleic anhydride capping agent ( MA) to improve the thermal stability of the PPC, then with polyethylene terephthalate -1,4 - cyclohexane dimethanol to ester (PETG) melt blending to prepare a good blend of the combined properties. The study found that (1) a nucleating agent (TMC-328) improved the the PLA crystallization properties, not only makes the PPC / PLA maintained the original better compatibility, but also to improve the mechanical properties of the system. TMC-328 to play in the the PLA crystallization process in the role of heterogeneous nucleation as well as refinement of the unit cell, adding 0.1% TMC-328, PLA cold crystallization temperature (Tcc) dropped to 111.40 from 126.14 ℃ pure PLA ° C, cold The crystallization enthalpy (△ Hcc) increased from 11.34 J / g to 23.49 J / g, at 100 ℃ complete crystallization time is shortened to about 12 min by 40min. Containing 0.3% TMC-328 PLA isothermal treatment at 100 ℃ under 5min, its degree of crystallinity can reach 40%. Comparing the data through of the PPC / PLA and PPC/PLA/TMC-328 for mechanical properties testing, TMC-328 added significantly to improve the brittleness of the PPC / PLA matrix, PPC/PLA/TMC-328 having a higher tensile strength, while also has a high elongation at break, wherein PPC / PLA (TMC-328) 70/30, the tensile strength increased from the original 15 Mpa to 16 Mpa, and the elongation at break from 164% to 344%. (2) PCL PPC / PLA system optimization, although PCL no PPC / PLA system compatibility contribute significantly, but PCL not only plays a role of nucleating agent in the crystallization process of the PLA also play a refinement of the unit cell, thereby improving the PPC / PLA / PCL films flexible, the PPC / PLA / PCL (70:30:2), a tensile strength of 25.92 MPa, compared PPC / PLA (70: 30) 15.41 Mpa increase of 10 MPa, elongation at break from 164.5% to 337.0%. (3) MA introduced to improve the thermal stability of the PPC, prevents the PPC terminal hydroxyl \PETG blend of the higher processing temperature, so as to further improve the mechanical properties and heat resistance of the PPC, and the PPC decomposition temperature (T-5%) from 161.0 ° C to 264.0 ° C. PETG content of ≤ 30% in PPC-MA/PETG blend, PETG as the island phase is uniformly dispersed in the substrate, PPC-MA, along with the the PETG content increased to 40%, PPC-MA/PETG blends have occurred sea ??- island \The tensile strength of the film of the PC-MA/PETG (70/30) from a pure PPC film material 4.7 Mpa to PPC-MA/PETG (70/30) film material of 16.93 MPa.
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