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Morphology control of polymer alloys is an attractive topic for investigators due to its ability to improve the performance of products for years. However, it is hard to control the morphology of immiscible polymer blends during melt processing. Herein, we studied the morphology evolution of poly(lactic acid) (PLA)/poly(butylene succinate) (PBS) with the inclusion of ethylene‐methyl acrylate‐glycidyl methacrylate (EGMA). Scanning electron microscopy of both cryo‐fractured and etched cryo‐fractured samples indicates that the in situ reaction among PLA, PBS, and EGMA can induce the morphology change and result in a novel 3D star‐like structure. Rheology behaviors of the samples under different angular frequencies were used to validate the formation of 3D networks in the samples. Tensile stiffness reinforcements at both room temperature and high temperature were provided through dynamic mechanical analysis. In addition, a 10‐fold improvement in impact strength is also monitored by the unnotched impact test to indicate the superior toughening effect. Furthermore, the crystalline behavior and thermal properties of the blends were also studied. It is believed that our work not only gives a deeper understanding of the reaction‐induced morphology evolution of the PLA/PBS/EGMA blends but also reveals an avenue toward morphology control by melt processing. [ABSTRACT FROM AUTHOR]

ABSTRACT: In this study, various poly(ethylene terephthalate) (PET) and linear low‐density polyethylene (LLDPE) with maleic anhydride‐grafted LLDPE (LLDPE‐g‐MAH) compatibilizer were melt blended under an elongational flow. A novel extrusion device, eccentric rotor extruder (ERE), was developed to supply such flow during the process. Including morphology, mechanical properties, melting behavior, and rheological behavior were studied. The morphological study showed that the compatibility between LLDPE and PET was greatly improved with LLDPE loading up to 80 wt %. Mechanical tests indicated that LLDPE could toughen PET to some extent. Moreover, a comparison of samples prepared between ERE and conventional extruder was made and demonstrated the sample prepared by ERE can exhibit better mechanical properties. Differential scanning calorimetry results revealed that PET can promote the crystallinity of LLDPE. Rheological behavior indicated that the complex viscosity of the blends exhibited strong shear thinning phenomenon with increasing LLDPE content, particularly in high‐frequency range blend with the LLDPE weight ratio of 80 wt % was more sensitivity to shear rate than neat LLDPE. The G′‐G″ curves of the blends also revealed that the microstructure of the blends changed significantly with the addition of LLDPE which was consistent with the scanning electron micrographs that PET particles became smaller and distributed more uniform with increasing LLDPE content. Furthermore, the blends showed similar stress relaxation mechanism with adding LLDPE content from 60 to 100 wt %. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46489. [ABSTRACT FROM AUTHOR]

ABSTRACT A novel mixer-vane mixer which is based on elongation flow was used to prepare high-density polyethylene (HDPE)/montmorillonite (MMT) nanocomposites without any additives. The effect of elongation flow on MMT intercalating in HDPE matrix was studied in terms of rotor speed and mixing time. X-ray diffraction and transmission electron microscope analyses showed that exfoliated and intercalated nanostructures were obtained when the rotor speed was 40 and 50 rpm, and mixing time was 6 minutes. For all samples prepared by vane mixer, MMT layers showed fine intercalation in the nanocomposites. Differential scanning calorimetry and thermogravimetric analysis were used to study the thermal properties of the nanocomposites. The results showed that the addition of MMT can improve the crystallization of the HDPE. Tensile test revealed the relationships between the mechanical properties and process parameters. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42600. [ABSTRACT FROM AUTHOR]

The technology of steam explosion was adopted to modify sisal fiber (SF) material and two different carbon particles, expanded graphite and conductive carbon black (CCB), were in situ coated on the surface of SF during steam explosion process. The DC conductivity and electromagnetic interference shielding effectiveness (SE) of the modified SF/polypropylene (PP) composites were studied and the measurement of electromagnetic interference (EMI) SE was conducted in two frequency ranges of 400-1,000 MHz and 1-18 GHz. The experimental results showed that this novel coating technology could improve the SE of the modified SF/PP composites significantly, which has a strong dependence on the loadings of the expanded graphite modified sisal fiber (SF-EG) and conductive carbon black modified sisal fiber (SF-CCB). When the loadings of SF-EG and SF-CCB reached 50 wt%, the maximum values of the SE were 33 dB and 51 dB, respectively. For the modified SF/PP composites, the experimental EMI SE values are in good correlation with the theoretical calculation values in far field of electromagnetic radiation. POLYM. COMPOS., 35:1038-1043, 2014. © 2013 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

The pressure establishment in the solid conveying section of a vane extruder was theoretically and experimentally studied in the present article. Based on the structural and conveying characteristics of the vane extruder, a four-plate model was developed. The effects of the device geometry (eccentricity ε and discharge port β), the polymer properties (different materials), and the operating conditions (temperature and rotating speed) on the pressure were also studied using a visual experimental device. The results showed that the experimental data were highly consistent with the theoretical data, which indicated that the theoretical model was sensible. Considering the optimization design of the device and its processing parameters, the eccentricity ε and the discharge port β of the discharge baffle should be appropriately selected, and the setting temperature of the feeding section should be set to a low value. The rotating speed of the rotor had no significant influence on the pressure establishment. In addition, the thermo-mechanical history of the vane extruder was shorter than that of the conventional screw extruder. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

The article discusses the results of a study which focused on the development of a model to analyze the pulsating distribution of total shear strain (TSS) of the melt in the single-screw vibration force field polymer extruders. The aim of the modeling technique was to increase the understanding about the time-dependent dynamic mixing process. The results showed that the TSS of melt in extruder increases upon the introduction of vibration. Larger TSS of melt improves the melt mixing process.