Guang Sheng Zeng

Effect of POSS on the Compatibility and Mechanical Properties of PC/PLA Blends

Polycarbonate/poly (lactic acid)/(PC/PLA) blends were modified by two kinds of POSS, glycidyl POSS (G-POSS) and Octa-ammonium POSS (O-POSS), respectively. The morphologies and mechanical properties of blends were investigated systematically. The results showed that the adding of O-POSS has a better effect on the compatibility of blend than adding G-POSS, the separate phase is invisible in the morphology of blends, and the mechanical properties of blends are improved significantly with the increase of added O-POSS.

Effect of AMPS and Clay on the Acrylic Acid Based Superabsorbent Hydrogels

A kind of superabsorbent hydrogels was synthesized by an optimized rapid solution polymerization of concertrated partically neutralized acrylic acid in the presence of an organic crosslinker agent under normal atmospheric conditions, 2-acrylamide-2-methyl propane sulfonic acid (AMPS) was added into the gels as co-polymerization monomer to enhance the ability of water absorption. Meanwhile, the hydrophilic nanosized clay Laponite XLG was also added into the gels for improving the shape stability and mechanical properties of gels. Through controlling the ratio of monomers and the content of nanosized clay, the superabsorbent hydrogels with excellent swelling ability and good mechanical properties could be gotten.

The Effect of Various Catalyzers on Transesterification in Reactive Blending PC/PLA Blends

Polycarbonate/Poly (lactic acid) blends were prepared through melt blending at the present of different kinds of organotin catalyzers such as monobutyltin oxide (MBTO), di-n-butyltinoxide (DBTO), di-n-octyltin oxide (DOTO), and dibutyltin dilaurate (DBTL). The effect of kind and mass of catalyzers on the properties of blends were investigated. The results showed that the DBTO is the most effective catalyzer on catalyzing the transesterification between PLA and PC, which corresponds to the analysis of morphologies and mechanical properties of blends. The use of DBTO could improve the compatibility and thus strengthen the mechanical properties of blends signficantly , and the optimal mass is 0.8wt% of blends.

Study on the Mechenical Properties of PPC/PLA Blends Modified by POSS

Aliphatic polycarbonate Polycarbonate/poly (lactic acid)/(PPC/PLA) blends were prepared by melt blending, 1,2-propanediol isobutyl POSS (P-POSS) were added into the blends as a compatilizer and reinforcer. The morphologies, mechanical properties and rheological properties of blends were investigated systematically. The results showed that the adding of P-POSS could improve the compatibilization of PPC and PLA obviously. The thermal stability of the blends was enhanced but the crystallization was effected slightly. Moreover, the tensile strength and impact strength of blends exhibited a considerably increase.

Preparation and Properties Research of PA6/PLA Blends Toughening Modified by TPU

Polyamide 6/Poly(lactic acid) (PA6/PLA) blends introduce the degradability of PLA to high performance PA6, but the bad toughness of both PA6 and PLA limits the application of blends. Aiming at this deficiency, thermoplastic polyurethane (TPU) was used as an additive for modifying the toughness of PA6/PLA blends. PA6/PLA/TPU blends at various compositions were prepared by melt blending, the effects of blend compositions on the morphology, thermal and mechanical properties of blends were investigated. The results showed that the addition of TPU improves the compatibilization between PA6 and PLA and makes the blends show more obvious plastic fracture behavior than PA6/PLA.When the content of PLA in PA6/PLA increases, the impact and tensile strength of blends decrease slightly with the intense decrease of the elongation at break, adding TPU into PA6/PLA blends strengthens the toughness of blends, but the tensile strength of blends decreases. Moreover, the crystallinity of PA6 /PLA blend is hampered by TPU.

Mechanical Performance and Microstructure of Plant Fiber Reinforced LDPE Foamed Composites

Plant fiber reinforced LDPE foamed composite was prepared with recycled corrugated paperboard, LDPE together with certain additives. The mechanical performances were tested and the effects of formula combinations on them were investigated. SEM was adopted to explore the effect of foaming agent on the microstructure of the composites. The results show that: 1) the tensile strength and bending strength increased while the notched impact strength and the elongation rate at break decreased with the plant fiber content. 2) The coupling agent LDPE-g-MAH could greatly improve the tensile strength and bending strength and the best mechanical performances were obtained at the coupling agent concentration of 5 wt% to that of plant fiber. 3) AC foaming agent brought down the density of the foamed composites, but the remerged cells became bigger and the tensile as well as bending strength declined with further over adding of AC. 4) the SEM observation showed a well-distributed cell size and more spherical cell shape as AC concentration going up within certain range.

Hysteresis Heat Build-up and Low Temperature Processing of Polymer under the Vibration Force Field

By using dynamic capillary and multi-dimensional vibration experiment desktop, isotactic polypropylene ( iPP ) is selected for the objective material to investigate the effect of the vibration parameters on the viscoelastic properties of polymer and its molding process. And a series conclusions can be draw that: The phase angle of polymer tends to decrease after a increase with vibration frequency increasing. The phase angle reach maximum value of 90° when the vibration frequency equals to the material natural frequency. Which polymer experience as pure viscous materials, also hysteresis heat build-up rate goes up to the peak. The plasticizing rate of polymer increase as the vibration amplitude, but the higher requirement for the equipment leveled up as well. The polymer plasticizing rate display the same law with that of phase angle against vibration frequency. When the vibration frequency equals to the material natural frequency, the plasticizing rate reach maximum. The investigation of this study will offers valuable theoretical references for polymer processing and novel equipment design in low-temperature.

The Forecast of Co-Rotating Twin-Screw Extruder's Screw Based on BP Neural Network Model

The established BP neural network model can forecast one of the wood-plastic composite molding equipment the screw of extruder with co-rotating twin-screw has been presented. The content of fiber and lubricant, the appropriate temperature of the extruder and the target yield are determined as the variable inputs, while the outputs are the diameters of the screw stem. This intelligent BP network model can forecast the condition of actual production precisely by setting the input properties of the material and the integration of products in order to fit the requirements of the wood-plastic composited production more successfully. Through the analysis of BP neural network model, the former simple method of choosing the screw stem’ diameters only depend on yield can be modified more efficiently.

The Properties of the Composites of Bamboo Flour and PVC

The composites based on polyvinyl chloride (PVC) and bamboo flour were made by extruded molding. The effects of the bamboo flour content on the composite physical properties were examined. The result showed that the composite mechanical properties were due to bamboo flour content. At the same time, we also make sure the process temperature and the proportional relationship between feed rate and screw speed is 1:2.

Study on the Crystallinity and Mechanical Properties of PC/PLA/LLDPE/ Montmorillonite Blends

Polycarbonate/poly (lactic acid)/(PC/PLA) blend is a kind of novel potential material for introducing the degradability of PLA to high performance PC. However, the bad compatibility between PC and PLA results in poor impact resistance and strength, which limits its applications. For resolving the problem, linear low density polyethylene (LLDPE) was added into blend to improve the mechanical properties, especially the toughness. Meantime, nanosized montmorillonite was also used as an additive for modifying the blend. The results showed that the the tensile and impact strength, the elongation at break of PC/PLA all be improved with the increase of LLDPE, the nanosized montmorillonite could also increase the strength of blends when the content is lower than wt5% of blends.