Preparation and Properties of Poly（lactic acid）/Polycaprolactone Degradable Multilayered Films Based on Micro⁃nano Multiplayer Coextrusion

doi:10.19491/j.issn.1001-9278.2021.11.002

Abstract

Abstract:

Poly（lactic acid）（PLA）/polycaprolactone （PCL） biodegradable multilayered films were prepared through a micro-nano layer multiplier coextrusion equipment， and their microstructure， mechanical properties and thermal stability were characterized by scanning electron microscopy， tensile and impact measurements， differential scanning calorimetry， and thermogravimetric analysis. The results indicated that the multilayered films exhibited better thermal stability and mechanical properties than the PLA/PCL blend films. PCL showed a significant toughening effect on the multilayered films， improving their crystallinity and thermal stability. When the PLA/PCL ratio was set as 40/60， 50/50 or 60/40， the multilayered films achieved good comprehensive properties with tensile strength of over 51.2 MPa， elongation at break of over 568.6 %， impact strength of over 100.7 J/m， PLA crystallinity of over 43.28 %， and thermal degradation peak temperature of over 373.22 ℃.

Key words: poly（lactic acid）, polycaprolactone, micro-nano layer multiplier coextrusion equipment, degradable multilayer film, mechanical property, thermal stability

CLC Number:

TQ 326.9

GU Lin, ZHU Yuting, HE Jialong, ZHU Huihao, MA Yulu, XIE Linsheng. Preparation and Properties of Poly（lactic acid）/Polycaprolactone Degradable Multilayered Films Based on Micro⁃nano Multiplayer Coextrusion[J]. China Plastics, 2021, 35(11): 7-14.

Figures/Tables 17

References 14

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样品种类	拉伸强度/MPa	断裂伸长率/%	冲击强度/J·m^-1
共混薄膜	48.3±1.7	495.7±12.6	89.7±2.9
微层薄膜	55.8±1.9	617.3±14.9	123.3±3.6

样品种类	拉伸强度/MPa	断裂伸长率/%	冲击强度/J·m^-1
共混薄膜	48.3±1.7	495.7±12.6	89.7±2.9
微层薄膜	55.8±1.9	617.3±14.9	123.3±3.6

样品	PCL				PLA
样品	T_c/°C	T_m/°C	ΔH_m/J·g^-1	X_c/%	T_cc/°C	T_m/°C	ΔH_m/J·g^-1	X_c/%
共混薄膜	28.88	55.96	33.13	48.72	101.08	167.15	20.54	43.90
微层薄膜	32.18	56.18	33.82	49.74	106.66	166.71	22.18	47.39

样品	PCL				PLA
样品	T_c/°C	T_m/°C	ΔH_m/J·g^-1	X_c/%	T_cc/°C	T_m/°C	ΔH_m/J·g^-1	X_c/%
共混薄膜	28.88	55.96	33.13	48.72	101.08	167.15	20.54	43.90
微层薄膜	32.18	56.18	33.82	49.74	106.66	166.71	22.18	47.39

PLA/PCL	PCL				PLA
PLA/PCL	T_c/°C	T_m/°C	ΔH_m/J·g^-1	X_c/%	T_cc/°C	T_m/°C	ΔH_m/J·g^-1	X_c/%
100/0	—	—	—	—	102.68	166.71	34.14	36.47
80/20	32.52	55.28	11.59	42.63	104.43	168.04	29.94	39.98
60/40	32.69	55.91	25.26	46.43	102.93	167.9	24.31	43.28
50/50	32.18	56.18	33.82	49.74	106.66	166.71	22.18	47.39
40/60	33.37	56.09	44.46	54.48	105.98	166.98	19.79	52.85
20/80	32.00	55.93	60.56	55.66	107.73	166.63	10.36	55.37
0/100	26.70	55.75	61.96	45.56	—	—	—	—