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compatibilizers in single step was sufficient. Moreover, the rate of shearing brought by the screw of the injection moulding machine was sufficient to ensure a dispersion of the disperse phase and a reduction of the interfacial tension. This study showed the possibility to compatibilize blends of HDPE and PET by injection moulding. This melt processing was interesting in an industrial because it permitted the transformation of a blend of polymers in one step. Guerrero, Lozano, Gonzalez, and Arroyo (2000) reported the effect of a compatibilizer on the mechanical properties of HDPE/PET blends. The blend of HDPE/PET in weight compositions of 75/25, 50/50, and 25/75 with and without compatibilizers were prepared in an internal mixer. The compatibilizer was a copolymer of ethylene and methacrylic acid partially neutralized with zinc (Surlyn). The olefinic part of Surlyn was compatible with HDPE, whereas the carboxylic end groups would form strong hydrogen bonds with carbonyl group of PET. There was no evidence of adhesion between two phases in the case of uncompatibilized blends. The viscosity of blends with Surlyn had increased. This indicated that there was less slippage at the interface. The addition of 7.5% of Surlyn in PET/HDPE (75/25 wt%) improved the elongation at break from 2.6 to 41.5% which was double of neat PET value. Izod impact strength of the blend also increased due to a high adhesion between two phases. Kim, Park, Kim, and Suh (2000) studied the compatibilization of HDPE/PET blends. High-density polyethylene grafted with the blocked isocyanate group (HDPE- g-BHI) was used as a reactive compatibilizer for an immiscible HDPE/PET blend. The blend ratios of the HDPE-g-BHI/PET or HDPE/PET were 90/10, 70/30, 50/50, 30/70, and 10/90 by weight. During the melt blending in an internal mixer, the chemical 9
eaction occurred between the isocyanate group and carboxyl or hydroxyl end groups of PET. SEM micrographs of cryogenically fractured surface in HDPE-g-BHI/PET blends exhibited that HDPE-g-BHI/PET blends had a much finer dispersion of the dispersed phase than that of HDPE/PET due to the decrement of the interfacial tension between the continuous and dispersed phases. An in situ-formed graft copolymer reduced interfacial tension and increased interfacial adhesion between the two phases. The tensile strength and elongation at break of reactive compatibilized blends showed higher values than those of uncompatibilized blends. The result was confirmed by dynamic mechanical analysis. The HDPE-g-BHI/PET blends showed a greater storage modulus than that of the HDPE/PET blends at the same composition. This result could be interpreted as due to the formation of an in-situ graft copolymer. DSC results for HDPE/PET and HDPE-g-BHI/PET at the compositions 30/70 and 10/90 blends showed that at the same composition appeared to be little difference in the endothermic heat by PET melting and the exothermic heat by PET crystallization. These results showed that the crystallinity of the continuous PET phase in the HDPE/PET blends remained unchanged regardless of the reactive compatibilization of the blocked isocyanate group grafted onto HDPE. Lusinchi, Boutevin, Torres, and Robin (2001) studied in situ compatibilization of HDPE/PET (60/40) blends by interfacial grafting of maleic anhydride (MA) without initiator in the molten state. The grafting reaction of MA onto HDPE was carried out in a batch mixer varying reaction parameters of the temperature, roller speed, and time of reaction. In a first step, the reactive copolymer was prepared in situ by grafting MA onto HDPE. In a second step, succinic anhydride reacted with functional end groups of PET. The in situ grafting of MA onto HDPE led to the 10
Page 1 and 2: A STUDY OF COMPATIBILIZATION AND PR
Page 3 and 4: A STUDY OF COMPATIBILIZATION AND PR
Page 5 and 6: ผสมปรับปรุง
Page 7 and 8: found more effective than PE-g-MA d
Page 9 and 10: TABLE OF CONTENTS VI Page ABSTRACT
Page 11 and 12: TABLE OF CONTENTS (Continued) VIII
Page 13 and 14: LIST OF TABLES Table Page 4.1 Densi
Page 15 and 16: LIST OF FIGURES (Continued) Figure
Page 17 and 18: LIST OF FIGURES (Continued) Figure
Page 19 and 20: to separate from the post-consumer
Page 21 and 22: absorption, tensile properties, fle
Page 23 and 24: 2.1 The study of compatibilization
Page 25: MA>E-MeA-g-MA. The different reacti
Page 29 and 30: compatibilized blends were improved
Page 31 and 32: HDPE was the dispersed phase, the d
Page 33 and 34: copolymer grafted with maleic anhyd
Page 35 and 36: SGF due to the very fast crystalliz
Page 37 and 38: Tjong, Xu, Yiu Li, and Mai (2002) i
Page 39 and 40: 2.4 Recycled plastic lumber Recycle
Page 41 and 42: stabilizers was effective in retain
Page 43 and 44: 3.1 Materials CHAPTER III EXPERIMEN
Page 45 and 46: stranded in a water bath before pel
Page 47 and 48: 3.3.2.2 Heat distortion temperature
Page 49 and 50: 3.3.5 Morphological properties Morp
Page 51 and 52: 600 800 1000 1200 1400 1600 1800 20
Page 53 and 54: Table 4.1 Density of HDPE, PET, and
Page 55 and 56: Table 4.2 Mechanical properties of
Page 57 and 58: 4.2.5 Thermal properties DSC curves
Page 59 and 60: HDT ( o C) 72.0 70.0 68.0 66.0 64.0
Page 61 and 62: Tensile strength (MPa) 60 50 40 30
Page 63 and 64: This is confirmed the incompatibili
Page 65 and 66: (f) (g) (h) Figure 4.10 SEM microgr
Page 67 and 68: O C O C O C O C O C O C O (CH 2 ) 2
Page 69 and 70: The IR spectra of the uncompatibili
Page 71 and 72: prevented. These crosslinking react
Page 73 and 74: Table 4.5 The effect of compatibili
Page 75 and 76: Flexural strength (MPa) Compressive
Page 77 and 78:
and polyester chains appeared to be
Page 79 and 80:
the presence of the compatibilizer.
Page 81 and 82:
The effects of the compatibilizer t
Page 83 and 84:
HDT of HDPE/PET compatibilized with
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The effect of the water absorption
Page 87 and 88:
Table 4.7 Density of the blends and
Page 89 and 90:
4.4.3 Mechanical properties Mechani
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4.4.4 Rheological properties The vi
Page 93 and 94:
values. This means that the presenc
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HDT of the blends and composites ar
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the composites after water immersio
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Table 4.10 Density and mechanical p
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the blends was found due to the pre
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Recommendation For Future Work The
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Bergeret, A., et al. (2001). The hy
Page 107 and 108:
Joshi, M., Maiti, S.N., and Misra,
Page 109 and 110:
Pawlak, A., Morawiec, J., Pazzagli,
Page 111:
BIOGRAPHY Sukunya Chareunkvun was b
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