The Effect of Polyquinone and Phenol-Phosphite Stabilizer on the Resistance of Polypropylene to Ionizing Radiation

2019 ◽  
Vol 816 ◽  
pp. 328-332 ◽  
Author(s):  
M.S. Lisanevich ◽  
Elvina R. Rakhmatullina ◽  
Yu.N. Khakimullin ◽  
Rezeda Yu. Galimzyanova ◽  
R.M. Akhmadullin ◽  
...  
Keyword(s):  
Ionizing Radiation ◽  
Medical Devices ◽  
Polymeric Materials ◽  
Melt Flow Index ◽  
Flow Index ◽  
Radiation Sterilization ◽  
Melt Flow ◽  
Medical Products ◽  
Degradation Temperature

For polymeric materials intended for the manufacture of disposable sterile medical devices, resistance to sterilization methods is important. For the manufacture of disposable medical products is widely used polypropylene, destructive during radiation sterilization. It is established that the addition of polyquinone leads to a decrease in the destruction of polypropylene, which is manifested in a decrease in the values of the melt flow index and an increase in the degradation temperature of polypropylene of the irradiated compositions.

PREDICTING THE FLOW PROPERTIES OF POLYAMIDE NANOCOMPOSITES BY USING VINOGRADOV-MALKIN MODEL

2015 ◽  
Vol 9 (3) ◽  
pp. 2446-2452
Author(s):  
Tomasz Mariusz Majka ◽  
Marcin Majka ◽  
Muhammad Kamrul Hasan
Keyword(s):  
Shear Rate ◽  
Flow Direction ◽  
Polymeric Materials ◽  
Melt Flow Index ◽  
Polyamide 6 ◽  
Flow Index ◽  
Melt Flow ◽  
Melt Flow Rate ◽  
Shear Rates ◽  
Different Temperatures

This article reports the prediction of the theoretical flow curves of polyamide composites by using Vinogradov-Malkin model. Determination of the melt flow index of polymeric materials is the first step to study viscosity-shear rate relationship. The viscosity of the composites at different temperatures were calculated by using the Williams, Landel'a and Ferry (WLF) equation. Other important rheological characteristics were calculated by using appropriate equations. One point method is employed to correlate the changes in viscosity with temperatures. As expected, it is found that incorporation of nanoclay to polyamide 6 (PA6) significantly decreases the Melt Flow Rate of the composites and hence, increases density. Addition of stabilizer further increases density of the PA6/nanoclay composites. The simulations of viscosity curves for PA6 composites were carried out at measurement temperature, 240°C and in the range of 180°C - 350°C with shear rate of 10-1 – 103 1/s. It is found that addition of nanoclay and stabilizer to PA6 decreases viscosity of the composites in the order of PA6/OMMT > PA6 > PA6/I1098 > PA6/OMMT/I1098 > PA6/MMT/I1098 > PA6/MMT. At higher shear rates, viscosity decreases in the same sequence as low shear rates. At further higher shear rates (> 1000 1/s), filler particles are arranged in the flow direction thus exerting no significant effect on viscosity of composites both with and without the stabilizer. During injection moulding in the shear rate ranging from 101 – 104 1/s at 240°C temperature, it is evident that viscosity decreases drastically with increase in shear rate.

scholarly journals Enhancement of mechanical, thermal and water uptake performance of TPU/jute fiber green composites via chemical treatments on fiber surface

e-Polymers ◽  
2020 ◽  
Vol 20 (1) ◽  
pp. 133-143 ◽  
Author(s):  
Tuffaha Fathe Salem ◽  
Seha Tirkes ◽  
Alinda Oyku Akar ◽  
Umit Tayfun
Keyword(s):  
Water Absorption ◽  
Water Uptake ◽  
Mechanical Test ◽  
Fiber Surface ◽  
Melt Flow Index ◽  
Jute Fiber ◽  
Morphological Properties ◽  
Flow Index ◽  
Melt Flow ◽  
Treatment Type

AbstractChopped jute fiber (JF) surfaces were modified using alkaline, silane and eco-grade epoxy resin. Surface characteristics of jute fibers were confirmed by FTIR and EDX analyses. JF filled polyurethane elastomer (TPU) composites were prepared via extrusion process. The effect of surface modifications of JF on mechanical, thermo-mechanical, melt-flow, water uptake and morphological properties of TPU-based eco-composites were investigated by tensile and hardness tests, dynamic mechanical analysis (DMA), melt flow index (MFI) test, water absorption measurements and scanning electron microscopy (SEM) techniques, respectively. Mechanical test results showed that silane and epoxy treated JF additions led to increase in tensile strength, modulus and hardness of TPU. Glass transition temperature (Tg) of TPU rose up to higher values after JF inclusions regardless of treatment type. Si-JF filled TPU exhibited the lowest water absorption among composites. Surface treated JFs displayed homogeneous dispersion into TPU and their surface were covered by TPU according to SEM micro-photographs.

Rheological Study on of PBT with High Melt Flow Index

2012 ◽  
Vol 487 ◽  
pp. 644-648
Author(s):  
Yuan Liu ◽  
Lin Wang ◽  
Qing Yan Xu ◽  
Pei Jie Lin ◽  
Zhi Hong Guo ◽  
...  
Keyword(s):  
Activation Energy ◽  
Shear Rate ◽  
Apparent Viscosity ◽  
Melt Flow Index ◽  
Flow Index ◽  
Melt Flow ◽  
Flow Activation Energy ◽  
Nonwoven Fabrics ◽  
Flow Activation ◽  
High Flexibility

Melt-blown generated PBT nonwoven fabrics usually have small fibril diameter, high flexibility, well heat and oil resistance. Therefore, they would have promising application such as vehicle filtering media. The rheological behavior of PBT with High Melt Flow Index for Melt-blown is investigated in this paper. It is a direction of the technology design and fabrication parameters .The relation of apparent viscosity and shear rate is analyzed, as well as flow activation energy and Non-Newtonian indexes. The results suggest that PBT with High Melt Flow Index is Non-Newtonian fluid. Apparent viscosity and flow activation energy show gradually decrease with increasing shear rate, exhibiting typical shear-thinning behavior.

From melt flow index to rheogram

1983 ◽  
Vol 22 (1) ◽  
pp. 90-101 ◽  
Author(s):  
A. V. Shenoy ◽  
S. Chattopadhyay ◽  
V. M. Nadkarni
Keyword(s):  
Melt Flow Index ◽  
Flow Index ◽  
Melt Flow

Characterization of microwave-treated oil palm empty fruit bunch/glass fibre/polypropylene composites

2015 ◽  
Vol 30 (7) ◽  
pp. 986-1002 ◽  
Author(s):  
MR Islam ◽  
A Gupta ◽  
M Rivai ◽  
MDH Beg
Keyword(s):  
Glass Fibre ◽  
Oil Palm ◽  
Melt Flow Index ◽  
Flow Index ◽  
Mechanical And Thermal Properties ◽  
Empty Fruit Bunch ◽  
Scanning Calorimetry ◽  
Fixed Temperature ◽  
Polypropylene Composites ◽  
Degradation Temperature

Composites were prepared from recycled polypropylene (RPP), oil palm empty fruit bunch (EFB) and/or glass fibre (GF) using extrusion and injection moulding techniques. Two types of maleic anhydride-grafted polypropylene such as Polybond 3200 and Fusabond P 613 were used to improve the interfacial adhesion between fibres and matrix. The EFB: GF ratio was fixed as 70:30 and fibre loading was considered as 40 wt%. Microwave was used to treat the EFB fibre, which was soaked in a fixed mass concentration (12.5%) of alkali solution at different temperatures (70, 80 and 90°C) for a fixed period of time (60 min) and for different times (60, 90 and 120 min) at a fixed temperature (90°C). A magnetron controller was developed to control the time and temperature accurately for the treatment of fibre. Various characterization techniques such as density, melt flow index, tensile, Izod impact, flexural, field-emission scanning electron microscopy and water uptake testing were performed for the composites. Besides, thermogravimetric analysis and differential scanning calorimetry were also used to evaluate the thermal and crystalline properties of the composites, respectively. Result analyses revealed that microwave-treated fibre-based composites showed improved mechanical and thermal properties. EFB fibres treated at 90°C for 90 min were found to be suitable for better reinforcement into the composite in terms of mechanical, thermal and crystalline properties. Moreover, onset degradation temperature and water absorption properties were also found to be changed apparently due to treatment.

scholarly journals Effect of Hard Plastic Waste on the Quality of Recycled Polypropylene Blends

Recycling ◽  
2021 ◽  
Vol 6 (3) ◽  
pp. 58
Author(s):  
Patrizio Tratzi ◽  
Chiara Giuliani ◽  
Marco Torre ◽  
Laura Tomassetti ◽  
Roberto Petrucci ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Polymeric Materials ◽  
Melt Flow Index ◽  
Plastic Waste ◽  
Flow Index ◽  
Yield Strain ◽  
Melt Index ◽  
Polypropylene Blends ◽  
Post Industrial ◽  
Plastic Containers

The recycling of plastic waste is undergoing fast growth due to environmental, health and economic issues, and several blends of post-consumer and post-industrial polymeric materials have been characterized in recent years. However, most of these researches have focused on plastic containers and packaging, neglecting hard plastic waste. This study provides the first experimental characterization of different blends of hard plastic waste and virgin polypropylene in terms of melt index, differential scan calorimetry (DSC), thermogravimetric analysis (TGA), mechanical properties (tensile, impact and Shore hardness) and Vicat softening test. Compared to blends based on packaging plastic waste, significant differences were observed in terms of melt flow index (about 10 points higher for hard plastic waste). Mechanical properties, in particular yield strain, were instead quite similar (between 5 and 9%), despite a higher standard deviation being observed, up to 10%, probably due to incomplete homogenization. Results demonstrate that these worse performances could be mainly attributed to the presence of different additives, as well as to the presence of impurities or traces of other polymers, other than incomplete homogenization. On the other hand, acceptable results were obtained for selected blends; the optimal blending ratio was identified as 78% post-consumer waste and 22% post-industrial waste, meeting the requirement for injection molding and thermoforming.

Thermomechanical investigations of PEKK-HAp-CS composites

2019 ◽  
Vol 233 (11) ◽  
pp. 1196-1203
Author(s):  
Rupinder Singh ◽  
Gurchetan Singh ◽  
Jaskaran Singh ◽  
Ranvijay Kumar ◽  
Md Mustafizur Rahman ◽  
...  
Keyword(s):  
Melt Flow Index ◽  
Extrusion Process ◽  
Flow Index ◽  
Fused Deposition Modelling ◽  
Index Test ◽  
Melt Flow ◽  
Scanning Calorimetry ◽  
Fused Deposition ◽  
Ether Ketone ◽  
Input Variables

In this experimental study, a composite of poly-ether-ketone-ketone by reinforcement of hydroxyapatite and chitosan has been prepared for possible applications as orthopaedic scaffolds. Initially, different weight percentages of hydroxyapatite and chitosan were reinforced in the poly-ether-ketone-ketone matrix and tested for melt flow index in order to check the flowability of different compositions/proportions. Suitable compositions revealed by the melt flow index test were then taken forward for the extrusion of filament required for fused deposition modelling. For thermomechanical investigations, Taguchi-based design of experiments has been used with input variables in the extrusion process as follows: temperature, load applied and different composition/proportions. The specimens in the form of feedstock filament produced by the extrusion process were made to undergo tensile testing. The specimens were also inspected by differential scanning calorimetry and photomicrographs. Finally, the specimen showing the best performance from the thermomechanical viewpoint has been selected to extrude the filament for the fused deposition modelling process.

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