scholarly journals A STUDY ON ENHANCING THE FLAME RETARDANCY OF POLYPROPYLENE YARN WITH BORON COMPOUNDS

2021 ◽  
Vol 2021 ◽  
pp. 378-384
Author(s):  
E. Eskiyapar ◽  
H.K. Kaynak ◽  
H.İ. Çelik ◽  
E. Sarıoğlu
Keyword(s):  
Particle Size ◽  
Flame Retardancy ◽  
Melt Spinning ◽  
Filament Yarn ◽  
Boron Compound ◽  
Powder Particle Size ◽  
Limiting Oxygen Index ◽  
Spinning Process ◽  
Yarn Structure ◽  
Textile Products

Functional properties such as; water resistance, flame retardancy, antibacterial efficiency etc. are required from textile products. One of the most commonly demanded products among functional textile products is the flame-retardant textiles. In this study, it is aimed to produce polypropylene filament yarn with permanent flame retardancy functionality by adding boron compound, which is Anhydrous disodium tetraborate powder (particle size < 38 micron), to the fiber structure during melt spinning process. In this study two different yarn samples are produced with anhydrous disodium tetraborate content by mass ratios of 2% and 5%. A control polypropylene filament yarn sample is also produced with no additive. By this way, three samples are produced by a conventional BCF polypropylene melt spinning machine with the same production parameters. Then, three knitted fabric samples were produced flat knitting machine. Limiting Oxygen Index (LOI) and vertical flammability tests were applied to the samples. According to results an important level of increase for LOI value is obtained with the sample which has 2% boron compound additive. Nevertheless, there is not a consistent effect of increasing boron content in yarn structure for LOI value. The reason of this situation may be resulted due to the uneven distribution of the boron compound in the yarn structure because of the particle size.

scholarly journals Modification and Compounding of CaMgAl-Layered Double Hydroxides and Their Application in the Flame Retardance of Acrylonitrile-Butadiene-Styrene Resin

Polymers ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 1623 ◽  
Author(s):  
Bai-nian Wang ◽  
Ming-yang Chen ◽  
Bao-jun Yang
Keyword(s):  
Mechanical Properties ◽  
Particle Size ◽  
Flame Retardancy ◽  
Layered Double Hydroxides ◽  
Acrylonitrile Butadiene Styrene ◽  
Expandable Graphite ◽  
Gravimetric Analysis ◽  
Limiting Oxygen Index ◽  
Double Hydroxides ◽  
Butadiene Styrene

CaMgAl-layered double hydroxides (CaMgAl-LDHs) were synthesized by a co-precipitation method to prepare sodium oleate-modified, borate-intercalated CaMgAl-LDHs (O-CaMgAl-LDHs) using in-situ intercalation and modification, and the LDHs samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FESEM), and thermal gravimetric analysis (TGA). The FESEM observations showed that the as-prepared CaMgAl-LDHs had a lamellar structure with a particle size of 200~500 nm, while the O-CaMgAl-LDHs had a plate-like structure with a particle size of about 100 nm. TGA showed that O-CaMgAl-LDHs resulted in higher thermal stability at high temperature compared to CaMgAl-LDHs. O-CaMgAl-LDHs/ABS composites were prepared by adding O-CaMgAl-LDHs to acrylonitrile-butadiene-styrene resin (ABS) to test the resulting flame retardancy and mechanical properties, and the results showed that the limiting oxygen index (LOI) could increase from 18% to 26%, while the mechanical properties decreased significantly when the added fraction was 40% (relative to ABS). O-CaMgAl-LDHs, ammonium polyphosphate (APP) and expandable graphite (EG) were added into the ABS to prepare ABS composites, and the effects of different compositions on the flame retardancy and mechanical properties of the ABS composites were investigated. The results showed that, when adding 5 g of O-CaMgAl-LDHs, 1 g of APP, and 14 g of EG into 40 g of ABS, the LOI of the ABS composite reached 28.8%, and the composite prepared could meet the V-0 grade requirements of the UL-94 combustion test, while the flexural strength decreased only 21.9% compared to pure ABS, the smallest decrease compared to all of the other composites.

scholarly journals Melt-Spinning of an Intrinsically Flame-Retardant Polyacrylonitrile Copolymer

Materials ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 4826
Author(s):  
Simon König ◽  
Philipp Kreis ◽  
Christian Herbert ◽  
Andreas Wego ◽  
Mark Steinmann ◽  
...  
Keyword(s):  
Flame Retardant ◽  
Flame Retardancy ◽  
Melt Spinning ◽  
Suspension Polymerization ◽  
Aqueous Suspension ◽  
Limiting Oxygen Index ◽  
Solution Spinning ◽  
Flame Retardant Properties ◽  
Flame Retardation ◽  
Pan Fibers

Poly(acrylonitrile) (PAN) fibers have two essential drawbacks: they are usually processed by solution-spinning, which is inferior to melt spinning in terms of productivity and costs, and they are flammable in air. Here, we report on the synthesis and melt-spinning of an intrinsically flame-retardant PAN-copolymer with phosphorus-containing dimethylphosphonomethyl acrylate (DPA) as primary comonomer. Furthermore, the copolymerization parameters of the aqueous suspension polymerization of acrylonitrile (AN) and DPA were determined applying both the Fineman and Ross and Kelen and Tüdõs methods. For flame retardancy and melt-spinning tests, multiple PAN copolymers with different amounts of DPA and, in some cases, methyl acrylate (MA) have been synthesized. One of the synthesized PAN-copolymers has been melt-spun with propylene carbonate (PC) as plasticizer; the resulting PAN-fibers had a tenacity of 195 ± 40 MPa and a Young’s modulus of 5.2 ± 0.7 GPa. The flame-retardant properties have been determined by Limiting Oxygen Index (LOI) flame tests. The LOI value of the melt-spinnable PAN was 25.1; it therefore meets the flame retardancy criteria for many applications. In short, the reported method shows that the disadvantage of high comonomer content necessary for flame retardation can be turned into an advantage by enabling melt spinning.

Preparation and characterizations of flame retardant melamine cyanurate/polyamide 6 composite fibers via in situ polymerization

2016 ◽  
Vol 87 (5) ◽  
pp. 561-569 ◽  
Author(s):  
Yuanyuan Li ◽  
Yunzhi Lin ◽  
Kai Sha ◽  
Ru Xiao
Keyword(s):  
Flame Retardant ◽  
Flame Retardancy ◽  
Melt Spinning ◽  
Cyanuric Acid ◽  
In Situ Polymerization ◽  
Polyamide 6 ◽  
Composite Fibers ◽  
Limiting Oxygen Index ◽  
Melamine Cyanurate

To improve the flame retardancy of polyamide 6 (PA6) fibers, melamine cyanurate (MCA)/PA6 composites were synthesized via in situ polymerization of ɛ-caprolactam in the presence of adipic acid-melamine salt and cyanuric acid-hexane diamine salt. The flame retardant MCA/PA6 composite fibers were prepared by melt spinning. The structure and properties of MCA/PA6 composites and MCA/PA6 composite fibers were studied by Fourier transform infrared spectra, X-ray diffraction, differential scanning calorimetry, thermogravimetric analysis, scanning electron microscopy, tensile tests, vertical burning tests (UL94) and limiting oxygen index (LOI) tests. Experimental results indicated that the MCA/PA6 composites loaded with 8 wt% of additives can achieve UL94 V-0 rating with an LOI value of 29.3%. The tenacity at break of PA6 fiber decreased from 4.85 to 3.11 cN·dtex–1 for MCA/PA6-8 composite fiber. However, the MCA/PA6 composite fibers can effectively suppress the propagation of flame in fabric. This means that the in situ polymerization approach paves the way for the preparation of MCA/PA6 composites that have good spinnability and flame retardancy.

scholarly journals Impact of MTA blend % in melt spinning process and polyester properties

2021 ◽  
Vol 3 (2) ◽  
Author(s):  
Puli Nageswar Rao ◽  
G. K. Sabavath ◽  
S. N. Paul
Keyword(s):  
Particle Size ◽  
Thermal Properties ◽  
Melting Point ◽  
Terephthalic Acid ◽  
Melt Spinning ◽  
Raw Materials ◽  
Carboxyl Groups ◽  
Fiber Breakage ◽  
Spinning Process ◽  
Purified Terephthalic Acid

AbstractIn Polyethylene terephthalate (PET) processing the raw materials are purified terephthalic acid (PTA), moderately purified terephthalic acid (MTA), monoehalene glycol (MEG). The processing of PTA is very difficult and costly. For reducing PTA percent we are using different percentages of MTA blend in PET processing. MTA affected the properties of polyester and melt spinning process. The properties such as elongation, tenacity, molecular chain length, b-color and IV, thermal properties, % carboxyl groups will change with MTA percentage. MTA percentage also affects fiber breakage percentage s, the melting point of PET. FTIR results show a change in chemical composition. Particle size, 4-CBA content of MTA affects the properties of the fiber.

Behavior of Microwave Heating of 316 Stainless Steel Green Body

2014 ◽  
Vol 936 ◽  
pp. 1694-1700
Author(s):  
Zhi Wei Li ◽  
Kai Yong Jiang ◽  
Fei Wang ◽  
Ji Liang Zhang
Keyword(s):  
Particle Size ◽  
Stainless Steel ◽  
Microwave Heating ◽  
Powder Particle ◽  
Microwave Power ◽  
Arc Discharge ◽  
Steel Powder ◽  
Powder Particle Size ◽  
Auxiliary Heating ◽  
316 Stainless Steel

This paper mainly introduces the mechanism of microwave heating: electric conduction loss, eddy current loss and arc discharge. The microwave heating behavior of 316 stainless steel powder body which made by gel casting was investigated in the paper. Experiments on different microwave power, powder particle size, and the content of auxiliary heating material showed that the smaller the powder particle size, the larger microwave power and auxiliary heating materials help 316 stainless steel body for sintering.

Effect of Crucible Parameters on Planar Flow Melt Spinning Process

2015 ◽  
Vol 68 (6) ◽  
pp. 1125-1129 ◽  
Author(s):  
M. Swaroopa ◽  
L. Venu Gopal ◽  
T. Kishen Kumar Reddy ◽  
B. Majumdar
Keyword(s):  
Melt Spinning ◽  
Planar Flow ◽  
Spinning Process

scholarly journals Effect of Particle Size Distribution on Powder Packing and Sintering in Binder Jetting Additive Manufacturing of Metals

2017 ◽  
Vol 139 (8) ◽  
Author(s):  
Yun Bai ◽  
Grady Wagner ◽  
Christopher B. Williams
Keyword(s):  
Particle Size ◽  
Additive Manufacturing ◽  
Large Degree ◽  
Full Density ◽  
Powder Particle Size ◽  
Powder Mixtures ◽  
Fine Powders ◽  
Sintering Shrinkage ◽  
The Impact ◽  
Binder Jetting

The binder jetting additive manufacturing (AM) process provides an economical and scalable means of fabricating complex parts from a wide variety of materials. While it is often used to fabricate metal parts, it is typically challenging to fabricate full density parts without large degree of sintering shrinkage. This can be attributed to the inherently low green density and the constraint on powder particle size imposed by challenges in recoating fine powders. To address this issue, the authors explored the use of bimodal powder mixtures in the context of binder jetting of copper. A variety of bimodal powder mixtures of various particle diameters and mixing ratios were printed and sintered to study the impact of bimodal mixtures on the parts' density and shrinkage. It was discovered that, compared to parts printed with monosized fine powders, the use of bimodal powder mixtures improves the powder's packing density (8.2%) and flowability (10.5%), and increases the sintered density (4.0%) while also reducing the sintering shrinkage (6.4%).

Tape Casting of BaTiO3

1984 ◽  
Vol 40 ◽  
Author(s):  
J. B. Blum ◽  
W. R. Cannon
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Glass Plate ◽  
Tape Casting ◽  
Phosphate Ester ◽  
Powder Particle Size ◽  
Drying Method ◽  
Ultrasonic Dispersion ◽  
The Past

AbstractFor the past two years we have been investigating the tape casting of BaTiO3 Specifically we have been interested in developing a useful tape casting formulation and procedure and in studying the effects of powder particle size distribution and dispersion processes on the forming of BaTiO3 tapes.The formulation we have developed is non-aqueous. An MEKethanol mixture is the solvent and an acrylic binder is used. Two dispersants are being used, a phosphate ester and Menhaden fish oil. Ultrasonic dispersion was found to be effective in breaking up weak powder agglomerates. We have found it important to add the dispersant before adding other organic components to obtain the best dispersion and strongest tapes. The drying method is also important to tape strength. The strongest tapes resulted when the tape was removed from the glass plate soon after casting. We have also demonstrated that for forming purposes a wide particle size distribution is preferred.

PLA/Carbon Nanotubes Multifilament Yarns for Relative Humidity Textile Sensor

2011 ◽  
Vol 6 (3) ◽  
pp. 155892501100600 ◽  
Author(s):  
Eric Devaux ◽  
Carole Aubry ◽  
Christine Campagne ◽  
Maryline Rochery
Keyword(s):  
Mechanical Properties ◽  
Carbon Nanotubes ◽  
Electrical Conductivity ◽  
Relative Humidity ◽  
Melt Spinning ◽  
Flexible Sensor ◽  
Spinning Process ◽  
Textile Sensor ◽  
Multifilament Yarns

Polylactide (PLA) was mixed with 4 wt.% of carbon nanotubes (CNTs) to produce electrical conductive multifilament yarns by melt spinning process for humidity detection. Thanks to a variation of electrical conductivity, this flexible sensor could detect the moisture presence. The introduction of plasticizer was necessary to ensure higher fluidity and drawability of the blend during the spinning process. The plasticizer modifies the crystallinity and the mechanical properties of the yarns. The effectiveness of this sensor (PLA/4 wt.% CNTs fibres) sensitive to humidity, is optimal when the spinning conditions are adapted. In this way, the temperature and the rate of the drawing roll were reduced. The influence of these parameters on the crystallinity, the mechanical properties and the sensitivity of the yarns were studied. Once the appropriate spinning conditions found, one humidity sensitive yarn was processed and the repeatability and efficient reversibility of its sensitivity were highlighted.

Sign in / Sign up

Export Citation Format

Share Document