Influence of multiple extrusions of blends made of polyethylene terephthalate and an oxygen scavenger on processing and packaging-related properties

2019 ◽  
Vol 36 (3) ◽  
pp. 260-284
Author(s):  
Sven Sängerlaub ◽  
Carlotta Elfi Glas ◽  
Daniel Schlemmer ◽  
Kajetan Müller
Keyword(s):  
Water Content ◽  
Intrinsic Viscosity ◽  
Test Methods ◽  
Absorption Capacity ◽  
Oxygen Absorption ◽  
Oxygen Scavenger ◽  
Scanning Calorimetry ◽  
Melt Flow Rate ◽  
Recycled Pet ◽  
The Impact

We investigated the influence of multiple extrusions of poly-(ethylene terephthalate) (PET) blended with a polymer-based oxygen scavenger. PET and PET blended with an oxygen scavenger additive were extruded up to four times to polymer strands. They were chilled in a water bath and cut to granules. Between the extrusions, the granules were dried at (only) 60°C to avoid the oxygen scavenger losing its reactivity. The water content was up to 0.5 wt.-% and therefore up to factor 100 higher than the recommended water content for PET extrusion. For further analysis, films were extruded and bottles were stretch-blow-molded. Due to polymer degradation and the recycled PET blend viscosity being too low, this material had to be blended with virgin PET in order to be processable. We used 33 wt.-% recycled PET and 66 wt.-% virgin PET ratio. The impact of the thermomechanical stress by multiple extrusions was investigated by several test methods: analysis of the melt pressure in the extruder barrel during extrusion, intrinsic viscosity and melt flow rate, microscopy, differential scanning calorimetry, color value measurements (L*a*b* values), tensile testing, compression testing, and oxygen absorption measurements. The intrinsic viscosity reduced after four re-extrusions in a compounder from 0.82 dl/g to 0.35 dl/g for PET with scavenger and to 0.41 dl/g for pure PET. This, even though low, difference can be explained by the slightly higher PET degradation due to the oxygen scavenger. We found slightly better mechanical properties (yield stress, Young’s modulus) for pure PET films compared to PET blended with an oxygen scavenger. At up to three extrusions, there was little influence on these properties. The extruded material with 3 wt.-% oxygen scavenger additive has an oxygen absorption capacity of 9.5 mg oxygen per 1 g of granules, i.e., the scavenger additive absorbed about 300 mg oxygen per 1 g of additive. Our results are relevant for in-house recycling processes of PET with oxygen scavenger.

Preparation and Property Study of PMMA/ASA Alloy

2011 ◽  
Vol 130-134 ◽  
pp. 2383-2387
Author(s):  
Guo Dong Tang ◽  
Si Chen ◽  
Yan Qin Shi ◽  
Xu Wang
Keyword(s):  
Flow Rate ◽  
Melt Blending ◽  
Dsc Analysis ◽  
Melt Flow ◽  
Scanning Calorimetry ◽  
Melt Flow Rate ◽  
Interface Phase ◽  
Blending Method ◽  
Method Effects ◽  
The Impact

Polymethyl methacrylate (PMMA)/ acrylonitrile-styrene-acrylate terpolymer (ASA) alloy was prepared via melt blending method. Effects of ASA melt flow rate and PMMA/ASA ratio on mechanical property of the alloy were studied. It showed that when the high melt flow rate ASA was used, alloy’s tensile strength and flexural strength were little different from using low melt flow rate ASA, while the impact strength was significantly higher than the latter. Differential scanning calorimetry (DSC) analysis showed that a glass transition (Tg) platform emerged in low melt flow rate ASA at 48.5°C, which represented the Tg of the interface phase formed between SAN grafted acrylate rubber particles and SAN matrix. Scanning electron microscope (SEM) experiment further showed that when low melt flow rate ASA was used, alloy’s cross section was smooth which showed the characteristics of brittle fracture.

scholarly journals Development of Flame-Retarded Nanocomposites from Recycled PET Bottles for the Electronics Industry

Polymers ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 233 ◽  
Author(s):  
Ferenc Ronkay ◽  
Béla Molnár ◽  
Ferenc Szalay ◽  
Dóra Nagy ◽  
Brigitta Bodzay ◽  
...  
Keyword(s):  
Large Scale ◽  
Scanning Calorimetry ◽  
Recycled Pet ◽  
Limiting Oxygen Index ◽  
Pet Bottles ◽  
Nucleation Effect ◽  
Flammability Test ◽  
Flame Retarded ◽  
Electronic Parts ◽  
The Impact

Recycled polyethylene-terephthalate (rPET) nanocomposites of reduced flammability were prepared by combining aluminum-alkylphosphinate (AlPi) flame retardant (FR) and natural montmorillonite (MMT), in order to demonstrate that durable, technical products can be produced from recycled materials. During the development of the material, by varying the FR content, the ratio and the type of MMTs, rheological, morphological, mechanical and flammability properties of the nanocomposites were comprehensively investigated. Related to the differences between the dispersion and nucleation effect of MMT and organo-modified MMT (oMMT) in rPET matrix, analyzed by Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Spectroscopy (EDS) and Differential Scanning Calorimetry (DSC), mechanical properties of the nanocomposites changed differently. The flexural strength and modulus were increased more significantly by adding untreated MMT than by the oMMT, however the impact strength was decreased by both types of nanofillers. The use of different type of MMTs resulted in contradictory flammability test result; time-to-ignition (TTI) during cone calorimeter tests decreased when oMMT was added to the rPET, however MMT addition resulted in an increase of the TTI also when combined with 4% FR. The limiting oxygen index (LOI) of the oMMT containing composites decreased independently from the FR content, however, the MMT increased it noticeably. V0 classification according to the UL-94 standard was achieved with as low as 4% FR and 1% MMT content. The applicability of the upgraded recycled material was proved by a pilot experiment, where large-scale electronic parts were produced by injection molding and characterized with respect to the commercially available counterparts.

Analysis of the Influence of Water Content on Shanxi Loess CBR and Rebound Module

2014 ◽  
Vol 919-921 ◽  
pp. 820-823
Author(s):  
Xi Rong Wu ◽  
Li Li Zhu
Keyword(s):  
Moisture Content ◽  
Water Content ◽  
Resilient Modulus ◽  
Test Methods ◽  
Shanxi Province ◽  
Influence Of Water ◽  
The Times ◽  
Relationship Of ◽  
The Impact ◽  
The Relationship

Selection of five typical loess in Shanxi Province, the paper adopt the indoor test methods to prepares the different compaction and different moisture content specimens which were used to test CBR value and rebound module, analyzes the impact of compactness and moisture content on the CBR value and resilient modulus and establishes the relationship of CBR and moisture content. The result shows that the level of moisture content has great impact on CBR value and rebound module. The CBR value is maximal under optimum moisture content and maximum degree of compaction condition. The times of compaction have little effect on the improvement of CBR with increasing water content. The relationship of the soaking CBR,resilient modulus and the moisture content shows a certain regularity.Key words: Loess filler;the CBR;resilient modulus;compactness;moisture content;relationship

scholarly journals Double-Function Oxygen Scavenger and Aromatic Food Packaging Films Based on LDPE/Polybutadiene and Peanut Aroma

Polymers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1310
Author(s):  
Adriana Juan-Polo ◽  
Salvador E. Maestre Pérez ◽  
María Monedero Prieto ◽  
Ana María Tone ◽  
Carmen Sánchez Reig ◽  
...  
Keyword(s):  
Thermal Properties ◽  
Food Packaging ◽  
Absorption Capacity ◽  
Metal Catalyst ◽  
Oxygen Absorption ◽  
Oxygen Scavenger ◽  
Retention Capacity ◽  
Oxygen Capacity ◽  
Double Function ◽  
The One

The aim of this study was to develop a double function active packaging material for nuts. The packaging solution, on the one hand, integrated polybutadiene (PB) as an oxygen scavenger and, on the other hand, it incorporated peanut aroma (PA) to improve customer’s sensorial experience. Different formulations based on low density polyethylene (LDPE), commercial PA (5 wt %) and PB at two levels (5 wt % and 13 wt %) were obtained by cast film extrusion. The obtained films were compared in terms of their mechanical, structural, optical and thermal properties confirming a plasticizing effect of PA and PB resulting in an increase in the ductility of the polymer and in a slight decrease in the thermal properties, maintaining their transparency. Regarding the oxygen capacity of the films, values of 4.4 mL and 2.7 mL O2 g−1 film were obtained for PE/PA/PB13 and PE/PA/PB5, respectively, after 6 days proving the suitability of the UV irradiation treatment in improving the oxygen absorption capacity of PB without the need of a metal catalyst. The aroma retention capacity into the polymer matrix was also evaluated in the developed formulations. The incorporation of PB in 13 wt % into a LDPE matrix improved the PA retention. This behavior was attributed to the ability of PB in enhancing cross-linking of LDPE as the concentration of PB increases. The results suggested the potential of PE/PB/PB13 films as oxygen scavenger and aromatic food packaging system to offer protection against lipid oxidation in nuts.

Experimental study on texturability of filament yarns produced from recycled PET

2020 ◽  
Vol 90 (23-24) ◽  
pp. 2703-2713
Author(s):  
Marjan Abbasi ◽  
Mohammad Reza Mohades Mojtahedi ◽  
Richard Kotek
Keyword(s):  
Experimental Study ◽  
Differential Scanning Calorimetry ◽  
Polyethylene Terephthalate ◽  
Intrinsic Viscosity ◽  
Similar Response ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Recycled Pet ◽  
Elongation At Break ◽  
X Ray

In the present work, the texturability of filament yarns produced from recycled bottle grade polyethylene terephthalate (R-PET) and new fiber grade PET (FG-PET) were investigated and compared experimentally. Yarn spun on a spin-draw spinning machine was draw-textured. Elongation at break in each fiber was set to reach 30 ± 5% in the texturing machine. The effect of the draw-texturing conditions on thermomechanical, structural, and crimp properties were examined. Draw-texturing behaviors of the fibers were analyzed using differential scanning calorimetry and measurements of intrinsic viscosity, mechanical and crimp properties, density, and X-ray diffraction. The results indicate that crystallinity of the textured yarn from R- PET and FG-PET has increased compared to the semi-drawn yarns. Further, the lateral dimensions of the R-PET crystals are relatively well developed. Crimp properties show nearly similar response for two polymer yarns for the texturing process. It was found that R-PET can be the premier feed supply for the draw-texturing process and that filaments with appropriate confidence could be obtained from the R-PET.

scholarly journals Application of the Calorimetric Methods to the Characteristics of Seeds from Olives

Proceedings ◽  
2020 ◽  
Vol 70 (1) ◽  
pp. 90
Author(s):  
Andrzej Bryś ◽  
Joanna Bryś ◽  
Marko Obranović ◽  
Dubravka Škevin ◽  
Szymon Głowacki ◽  
...  
Keyword(s):  
Olive Oil ◽  
Water Content ◽  
Cooling System ◽  
Waste Product ◽  
Normal Pressure ◽  
Ash Content ◽  
Initial Water Content ◽  
Scanning Calorimetry ◽  
Initial Water

The olive oil industry represents an important productive sector in the Mediterranean basin countries. Olive stone is an essential by-product generated in the olive oil extraction industries and it represents roughly 10% by weight of the olive fruit. The seeds of pickled olives are also a significant waste product. In the present study, we have investigated the possibility of the use of differential scanning calorimetry for the thermal characterization of seeds from green and black pickled olives from Croatia. The differential scanning calorimeter (DSC) with a normal pressure cell equipped with a cooling system was used to determine the thermal properties of seeds from olives. The following analyses were also performed: the determination of calorific values in a pressure bomb calorimeter, the determination of initial water content, the determination of changes of water content during drying at the temperatures of 30 °C, 50 °C and 80 °C, the determination of a percentage content of seeds mass to the mass of the whole olives, and the determination of ash content. Seeds from olives are characterized by very good parameters as a biomass. The analyzed olive seeds were characterized by low water content, low ash content, and a relatively high caloric value.

scholarly journals Improving Rheological and Mechanical Properties of Various Virgin and Recycled Polypropylenes by Blending with Long-Chain Branched Polypropylene

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1137
Author(s):  
Sascha Stanic ◽  
Thomas Koch ◽  
Klaus Schmid ◽  
Simone Knaus ◽  
Vasiliki-Maria Archodoulaki
Keyword(s):  
Mechanical Properties ◽  
Molecular Weight ◽  
Tensile Test ◽  
Reactive Extrusion ◽  
Original Material ◽  
Melt Flow Rate ◽  
Single Screw Extruder ◽  
Pp Blends ◽  
The Impact ◽  
Long Chain

Blends of two long-chain branched polypropylenes (LCB-PP) and five linear polypropylenes (L-PP) were prepared in a single screw extruder at 240 °C. The two LCB-PPs were self-created via reactive extrusion at 180 °C by using dimyristyl peroxydicarbonate (PODIC C126) and dilauroyl peroxide (LP) as peroxides. For blending two virgin and three recycled PPs like coffee caps, yoghurt cups and buckets with different melt flow rate (MFR) values were used. The influence of using blends was assessed by investigating the rheological (dynamic and extensional rheology) and mechanical properties (tensile test and impact tensile test). The dynamic rheology indicated that the molecular weight as well as the molecular weight distribution could be increased or broadened. Also the melt strength behavior could be improved by using the two peroxide modified LCB-PP blends on the basis of PODIC C126 or PEROXAN LP (dilauroyl peroxide). In addition, the mechanical properties were consistently enhanced or at least kept constant compared to the original material. In particular, the impact tensile strength but also the elongation at break could be increased considerably. This study showed that the blending of LCB-PP can increase the investigated properties and represents a promising option, especially when using recycled PP, which demonstrates a real “up-cycling” process.

scholarly journals Water Absorption Capacity Determines the Functionality of Vital Gluten Related to Specific Bread Volume

Foods ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 228
Author(s):  
Marina Schopf ◽  
Katharina Anne Scherf
Keyword(s):  
Water Absorption ◽  
Water Content ◽  
Wheat Flour ◽  
Specific Volume ◽  
Disulfide Bonds ◽  
Protein Composition ◽  
Absorption Capacity ◽  
Water Absorption Capacity ◽  
Water Addition ◽  
Wheat Flours

Vital gluten is often used in baking to supplement weak wheat flours and improve their baking quality. Even with the same recipe, variable final bread volumes are common, because the functionality differs between vital gluten samples also from the same manufacturer. To understand why, the protein composition of ten vital gluten samples was investigated as well as their performance in a microbaking test depending on the water content in the dough. The gluten content and composition as well the content of free thiols and disulfide bonds of the samples were similar and not related to the specific bread volumes obtained using two dough systems, one based on a baking mixture and one based on a weak wheat flour. Variations of water addition showed that an optimal specific volume of 1.74–2.38 mL/g (baking mixture) and 4.25–5.49 mL/g (weak wheat flour) was reached for each vital gluten sample depending on its specific water absorption capacity.

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