PC / PMMA sheet production line based on blending of POM and TPU
DATE：2021/7/2 8:35:21 / READ： / SOURCE：This station
PC / PMMA sheet production line based on blending of POM and TPU
POM / TPU blends can be prepared by blending polyurethane elastomer with POM at 190 ℃. The POMS used are duracon M-90 (pom-1) and duracon m-270 (pom-2), respectively. The tensile strength of the blends decreased with the increase of TPU, and the elongation at break reached the highest value when the TPU content was 25%. The elastic modulus and molding shrinkage of the blends decreased with the increase of TPU. The stress-strain curves of POM / TPU blends prepared by mixing at 170 ~ 200 ℃ are shown in Fig. 6-13. The results showed that the elongation at break increased significantly with the increase of TPU content. PC / PMMA sheet production line www.handern.comThe tensile strength of TPU / POM blends decreased with the increase of TPU BL and the decrease of POM, and the impact strength of TPU / POM blends increased with the increase of TPU. When POM / TPU (90 / 4010) was used, the fracture strength of the blends was 56.31mpa, and the notched impact strength of the blends was 123.15j/m; When POM / TPU (40 / 60) was used, the fracture strength of the blends decreased to 25.12mpa, the tensile strength of 1.02.05.0115695/0tpu/pom blends decreased with the increase of TPU and the decrease of POM, and the impact strength of the blends increased with the increase of TPU. When POM / TPU (90 / 10) was used, the fracture strength of the blend was 56.31mpa and the notched impact strength of the cantilever beam was 123.15j/m; When POM / TPU (40 / 60) was used, the fracture strength of the blends decreased to 25.12mpa, and the notched impact strength of the blends increased to 140.00j/m. The yield strength and tensile strength of the blends decrease with the increase of TPU, and the notched impact strength of the blends reaches the highest value when POM / TPU (70 / 30) is used. The notched impact strength of POM / TPU (100 / 30) blends reaches 140 J / m at 0 ℃, while that of POM / TPU (100 / 10) blends is only 80 J / m. In addition, the tensile strength of TPU / POM blends decreases with the increase of TPU, and the elongation at break increases with the increase of TPU www.handern.com
POM (M90, Shanghai solvent factory) and TPU (jm80a, Tianjin polyurethane factory) were blended. The addition of TPU increased the impact strength of the system, and a maximum value appeared when the TPU content was 10 phr (mass fraction), which was 385% higher than that of pure POM. This was due to the decrease of crystallization rate and internal stress of POM due to the addition of TPU. The peak can be explained by the generally accepted "craze shear band" theory and the morphology of the blends. When the TPU content is 10 phr, the TPU dispersed in the continuous phase of POM is spherical particles with small particle size and uniform dispersion, forming a continuous supramolecular structure. At this time, the impact strength of the system reaches the maximum. With the increase of TPU, the spherical particles of TPU become larger, resulting in the decrease of dispersion uniformity. Although the effect of stopping crazing is better with larger particle size, the contact area between TPU and POM is also reduced, which is not conducive to the improvement of impact strength. It can be seen that there is an optimum distribution area for the size, shape and size distribution of the particles in the continuous phase and dispersed phase. When the TPU content is 10 phr, the blends are in the best distribution region and the impact strength reaches the maximum. In addition, the addition of TPU decreased the tensile strength of the system. This may be due to the decrease of crystallinity and strength of TPU, and the low tensile strength of TPU. PC / PMMA sheet production line www.handern.com
The melt flow rate of the blends decreased with the increase of TPU content, and the viscosity of the blends decreased with the increase of shear rate, showing the pseudoplastic characteristics of the blends. With the increase of TPU content, the viscosity of the blends increased gradually. This may be due to the high viscosity of TPU itself, and the formation of hydrogen bond between POM and TPU, resulting in a certain cross-linking, which leads to the increase of intermolecular entanglement, resulting in the increase of flow resistance, that is, the decrease of fluidity. PC / PMMA sheet production line www.handern.com
The dynamic mechanical properties of POM / TPU blends were studied by means of dynamic viscoelastometer. The T of POM, TPU and POM / TPU blends can be measured and the compatibility of the blends can be judged. The T of POM and TG of TPU were - 86.3 ℃ and - 44 ℃ respectively. When the TPU content was 30 phr (mass fraction), there were two peaks on the tand curve at - 83.1 ℃ and - 47 ℃ respectively. It can be seen that there are two T in POM / TPU blends. A little closer to each other. This indicates that the blends of POM and TPU are basically incompatible, but there is a certain interaction between the two phases. PC / PMMA sheet production line www.handern.com
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