scholarly journals Multifunctional Polymer Composites Produced by Melt-Blown Technique to Use in Filtering Respiratory Protective Devices

Materials ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 712 ◽  
Author(s):  
Agnieszka Brochocka ◽  
Aleksandra Nowak ◽  
Katarzyna Majchrzycka ◽  
Michał Puchalski ◽  
Sławomir Sztajnowski

In this work, a multifunctional polymer composite is made using melt-blowing technology from polypropylene (88 wt.%) and poly (ethylene terephthalate) (12 wt.%) with the addition of functional modifiers, that is, 3 g of a superabsorbent polymer and 5 g of a biocidal agent (Biohaloysite). The use of modifiers is aimed at obtaining adequate comfort when using the target respiratory protection equipment (RPE) in terms of microclimate in the breathing zone and protection against harmful aerosols including bioaerosols. The developed production method is innovative in that the two powdered modifiers are simultaneously applied in the stream of elementary polymeric fibers by two independent injection systems. Aerosols of the modifiers are supplied via a specially designed channel in the central segment of the die assembly, reducing the amount of materials used in the production process and saving energy. The results show that the proposed method of incorporating additives into the fiber structure did not adversely affect the protective and functional properties of the resulting filtration nonwovens. The produced nonwoven composites are characterized by SEM, FTIR, and differential scanning calorimetry (DSC). Given their high filtration efficiency at 5%, satisfactory airflow resistance (~200 Pa), very good antimicrobial activity, and excellent water absorption capacity, the obtained multifunctional nonwoven composites may be successfully used in filtering respiratory protective devices.

2021 ◽  
Vol 22 (7) ◽  
pp. 3491
Author(s):  
Grażyna B. Dąbrowska ◽  
Zuzanna Garstecka ◽  
Ewa Olewnik-Kruszkowska ◽  
Grażyna Szczepańska ◽  
Maciej Ostrowski ◽  
...  

Plastic pollution is one of the crucial global challenges nowadays, and biodegradation is a promising approach to manage plastic waste in an environment-friendly and cost-effective way. In this study we identified the strain of fungus Trichoderma viride GZ1, which was characterized by particularly high pectinolytic activity. Using differential scanning calorimetry, Fourier-transform infrared spectroscopy techniques, and viscosity measurements we showed that three-month incubation of polylactide and polyethylene terephthalate in the presence of the fungus lead to significant changes of the surface of polylactide. Further, to gain insight into molecular mechanisms underneath the biodegradation process, western blot hybridization was used to show that in the presence of poly(ethylene terephthalate) (PET) in laboratory conditions the fungus produced hydrophobin proteins. The mycelium adhered to the plastic surface, which was confirmed by scanning electron microscopy, possibly due to the presence of hydrophobins. Further, using atomic force microscopy we demonstrated for the first time the formation of hydrophobin film on the surface of aliphatic polylactide (PLA) and PET by T. viride GZ1. This is the first stage of research that will be continued under environmental conditions, potentially leading to a practical application.


Materials ◽  
2018 ◽  
Vol 11 (8) ◽  
pp. 1397 ◽  
Author(s):  
Elaine dos Santos ◽  
Marcus Fook ◽  
Oscar Malta ◽  
Suédina de Lima Silva ◽  
Itamara Leite

Purified clay was modified with different amounts of alkyl ammonium and phosphonium salts and used as filler in the preparation of PET nanocomposites via melt intercalation. The effect of this type of filler on morphology and thermal and mechanical properties of PET nanocomposites was investigated by X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric analyses (TG), tensile properties, and transmission electron microscopy (TEM). The results showed that the mixture of alkyl ammonium and phosphonium salts favored the production of PET nanocomposites with intercalated and partially exfoliated morphologies with slight improvement in thermal stability. In addition, the incorporation of these organoclays tended to inhibit PET crystallization behavior, which is profitable in the production of transparent bottles.


Polymers ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 937 ◽  
Author(s):  
Niki Poulopoulou ◽  
George Kantoutsis ◽  
Dimitrios N. Bikiaris ◽  
Dimitris S. Achilias ◽  
Maria Kapnisti ◽  
...  

Poly(butylene 2,5-furandicarboxylate) (PBF) constitutes a new engineering polyester produced from renewable resources, as it is synthesized from 2,5-furandicarboxylic acid (2,5-FDCA) and 1,4-butanediol (1,4-BD), both formed from sugars coming from biomass. In this research, initially high-molecular-weight PBF was synthesized by applying the melt polycondensation method and using the dimethylester of FDCA as the monomer. Furthermore, five different series of PBF blends were prepared, namely poly(l-lactic acid)–poly(butylene 2,5-furandicarboxylate) (PLA–PBF), poly(ethylene terephthalate)–poly(butylene 2,5-furandicarboxylate) (PET–PBF), poly(propylene terephthalate)–poly(butylene 2,5-furandicarboxylate) (PPT–PBF), poly(butylene 2,6-naphthalenedicarboxylate)-poly(butylene 2,5-furandicarboxylate) (PBN–PBF), and polycarbonate–poly(butylene 2,5-furandicarboxylate) (PC–PBF), by dissolving the polyesters in a trifluoroacetic acid/chloroform mixture (1/4 v/v) followed by coprecipitation as a result of adding the solutions into excess of cold methanol. The wide-angle X-ray diffraction (WAXD) patterns of the as-prepared blends showed that mixtures of crystals of the blend components were formed, except for PC which did not crystallize. In general, a lower degree of crystallinity was observed at intermediate compositions. The differential scanning calorimetry (DSC) heating scans for the melt-quenched samples proved homogeneity in the case of PET–PBF blends. In the remaining cases, the blend components showed distinct Tgs. In PPT–PBF blends, there was a shift of the Tgs to intermediate values, showing some partial miscibility. Reactive blending proved to improve compatibility of the PBN–PBF blends.


2013 ◽  
Vol 773 ◽  
pp. 530-533
Author(s):  
Chen Liu ◽  
Xiang Hui Lu ◽  
Xue Qi ◽  
Peng Li

The melting and recrystallization behavior of Poly(ethylene terephthalate) (PET)/ Attapulgite(At)nanocomposites after isothermal crystallization from the melt was studied by Step-scan differential scanning calorimetry (SDSC). The influence of At contents, crystallization temperature and crystallization time on the melting process were examined. Two melting endotherms(in the SDSC CP.A curves, reversible part) and one recrystallization exotherm (in the SDSC CP.IsoK curves, irreversible part)of PET/At nanocomposites after isothermal crystallization were observed during the melt process. This ascribes to the melting-recrystallization mechanism .The low temperature endotherm attributes to the melting of primary crystal formed during the isothermal treating and the high temperature endotherm resulting from the melting of recrystallization materials. The reason why more recrystallization happened with the increase of At content was given and the process of recrystallization was described in detail. The effects of crystal perfection and recrystallization were minimized by increasing of crystallization temperature and time.


2010 ◽  
Vol 44-47 ◽  
pp. 2409-2413 ◽  
Author(s):  
Yu Sun ◽  
Guo Zheng ◽  
Hong Xiang Yang ◽  
Yan Jun Liu ◽  
Xiao Ning Li

This study investigated the thermal properties of ester-type easy cationic dyeable poly(ethylene terephthalate) (ECDP) polymers using differential scanning calorimetry (DSC), therogravimetric analysis (TGA). The mass ratios of 5-sodium sulfo bis(-hydroxyethyl) isophthalate(SIPE) for ECDP polymers were 2.8%, 5.5%, 6.8%, respectively. The fourth monomers were diethylene glycol adipate (DGA), diethylene glycol succinate (DGS) and diethylene glycol subacate (DES) with different contents. The results suggested that the Tg of ester-type ECDP decreased with the increasing the molecule weight of the fourth monomer at fixed SIPE and fourth monomer contents. The Tch of ECDP polymer to be lower than that of the CDP polymer with the same SIPE content. And it decreased as SIPE and fourth monomer contents increased, it also decreased with the increasing of the molecule weight of the fourth monomer given the same SIPE content. The effect of the ester-type soft segments reduced the Tm of ECDP. The thermal stability of ECDP polymer was less than PET and CDP polymers, and it decreased with increasing SIPE content, but increased with the ester-type fourth monomer content increasing.


1992 ◽  
Vol 36 ◽  
pp. 379-386
Author(s):  
T. Blanton ◽  
R. Seyler

The effect of dimethyl-5-sodiosulfoisophthalate, SIP, on poly(ethylene terephthalate), PET, crystallization has been studied using in situ high-temperature x-ray diffraction, HTXRD. At low levels of SIP modification, PET-like crystallinity was observed. At high SIP levels, clustering of polyester ionomers was observed and crystallization was significantly suppressed. The HTXRD data along with differential scanning calorimetry, DSC, and small angle x-ray scattering, SAXS, indicate that the change from bulk crystallization to bulk ionomer formation occurred when 8-12 mol% of the diester linkages contained SIP.


2014 ◽  
Vol 665 ◽  
pp. 331-334
Author(s):  
Xue Ming Cai ◽  
Shi Hong Li ◽  
Pan Jin Jia ◽  
Ming Tao Run

Poly (ethylene terephthalate)/poly (trimethylene terephthalate) (PET/PTT) blends were prepared and their melting and crystallization properties were investigated by differential scanning calorimetry (DSC). The glass transition temperatures suggest apparently that PET and PTT have good miscibility at amorphous state. The blends with more PET content less likely undergo a melting/recrystallization process during DSC heating scan. In the blends, PET component with higher supercooling degree will crystallize first, and then the crystallites of PET will be the nucleating agents for PTT, which greatly improves the crystallization rate of PTT.


1994 ◽  
Vol 347 ◽  
Author(s):  
Jianghua Wei ◽  
Richard Delgado ◽  
Martin C. Hawley ◽  
Mark T.Demeuse

ABSTRACTDielectric properties of poly(ethylene terephthalate) (PET) were measured over a frequency range of 10 KHz to 2.45 GHz and a temperature range of 20 to 110°C. Relaxation peaks were identified at 1) fixed frequency with variable temperatures, and 2) fixed temperature with variable frequencies. The crystallinity of poly (ethylene terephthalate) was measured using differential scanning calorimetry (DSC). Relationships between crystallinity, dielectric properties, and location of the dielectric relaxation peak on the frequency and temperature scales were studied for poly(ethylene terephthalate). Also, the dielectric loss factor decreases with increased crystallinity at 2.45 GHz and 4 GHz within the temperature range studied.


Sign in / Sign up

Export Citation Format

Share Document