A sustainable process to 100%bio-based nylons integrated chemical and biological conversion of lignocellulose

Considerable progress has been made in recent years to the development of sustainable polymers from bio-based feedstocks.In this study,100%bio-based nylons were prepared via an integrated chemical and biological process from lignocellulose.These novel nylons were obtained by the melt polymerization of 3-propyladipic acid derived from lignin and 1,5-pentenediamine/1,4-butanediamine derived from carbohydrate sugar.Central to the concept is a three-step noble metal free catalytic chemical funnelling sequence(Raney Ni mediated reductive catalytic fractionation-reductive funnelling-oxidative funnelling),which allowed for obtaining a single component 3-propyladipic acid from lignin with high efficiency.The structural and thermodynamic properties of the obtained nylons have been systematically investigated,and thus obtained transparent bio-based nylons exhibited higher Mw(>32,000)and excellent thermal stability(Td5%>265℃).Considering their moderate Tg and good melt strength,these transparent bio-based nylons could serve as promising functional additives or temperature-responsive materials.

Evaluation of Nylon 6 and Nylon 66 Cord Fabrics for Scooter Tyre Production under Different Curing Conditions

Cord fabric is a critical material used in the manufacture of tyres and various composite materials to increase durability and strength. The tyre consists of many layers of cord fabric, with each layer being referred to as a cord ply. These layers are strategically positioned within the tyre’s internal structure, particularly in the tread and sidewall areas, to improve handling, durability and impact resistance. The cord fabric also serves a critical role in maintaining the structural integrity of the tyre, ensuring that it retains its contour and resists deformations under different operating conditions. This study discusses the advantages and disadvantages of using Nylon 6 (NY6) and Nylon 66 (NY66) cord fabrics in scooter tire production, with a focus on their mechanical behavior under varying curing temperatures and pressures. It was observed that while the curing time for both NY6 and NY66 remained consistent across different platen temperatures and pressures, their mechanical properties showed significant differences. NY6, known for its flexibility and impact resistance, exhibited greater changes in cord-breaking strength and elongation with increasing temperature, showing a marked decrease in breaking strength at higher temperatures. In contrast, NY66 maintained better stability and performance under similar conditions.

NILIT enabling nylon recycling through products and partnership

Migdal Haemek,Israel,April 2,2024.NILIT,the global market leader,and a producer of high quality Nylon 6.6 for apparel and owner of the SENSIL?brand,introduces SENSIL?Flow,a new approach to Nylon 6.6 circularity that enables yarn,fabric,and,ultimately,apparel recycling to eliminate waste and further reduce apparel’s environmental impact.SENSIL?Flow is more than just a sustainable performance product.It is an innovative approach that engages the entire supply chain to truly attain circularity through product design and partnership.

Fabrication and Tissue Anchoring Performance of Nylon and Polypropylene Barbed Surgical Sutures

Barbed surgical sutures have attracted worldwide attention in recent years. The plurality of barbs projecting out and penetrating into surrounding tissue eliminates the need for tying a knot. In the current study,nylon and polypropylene( PP) barbed sutures with two different barb geometries designed to anchor in porcine skin and tendon tissues were fabricated by a specially designed mechanical cutting machine. The tensile properties were compared between the barbed and unbarbed control sutures. The in vitro tissue anchoring ability was measured by two tissue /suture pullout tests,one for skin and the other for tendon tissue. Regardless of the type of tissue,the PP barbed suture with its higher modulus had a superior anchoring ability. Given the same suture material,improved anchoring performance was shown in tendon tissue.

Nylon innovation to a new height!The digital person“Rong”lights up the fiber highlight moment

Fujian Eversun Jinjiang Co.,Ltd.(hereinafter referred to as“Eversun Jinjiang”)and China International Fabrics Design Competition once again jointly set up the“Nylon Product Development&Application Prize”in 2023.After three consecutive years of growth,the award has brought together high-quality nylon products and high-level fabric development enterprises,and accelerated the process of industrial chain coordination and high-quality development.At the 2023 China International Fabrics Design Competition award ceremony held on August 28,fabrics from six outstanding textile enterprises respectively won the Fashion Color Award for Nylon Fabric,Innovation Award for Nylon Fabric Development,and Market Application Award for Nylon Fabric.The six award-winning fabrics in color,style,feel,technology,function,product fancy application has reached a new level compared to previous years.

Nylon6复合材料的阻燃性能研究

针对目前无机阻燃剂对Nylon6阻燃效果差的研究现状,考察了滑石粉、MCA、有机蒙脱土含量对Nylon6复合材料力学性能和阻燃性能的影响.研究结果表明:随着三种阻燃剂用量的增加,Nylon6拉伸强度都有不同程度的增加,其中添加MCA的拉伸强度增加最明显,从纯Nylon6的78.13 MPa增加到90.65 MPa,增加了16%;随着阻燃剂用量的增加,Nylon6冲击强度和熔融指数都有下降;当有机蒙脱土含量为10%时,Nylon6复合材料的氧指数由20.71升高到27.89,增加了35%,继续增加有机蒙脱土用量,氧指数增加不明显.

Wingsuit Flying

Wingsuit Flying,alsocalled wingsuiting,is a variation of skydiving.In this sport,a person will fly in the air using a special jumpsuit called a wingsuit.This wingsuit comprises of two arm wings and a single leg wing which has inflatable nylon cells.The modern wingsuits were developed in the 1990's.They are sometimes referred to as birdman suits or flying squirrel suits.

助剂Levegal FTS在Telon类染料上染Nylon的应用

介绍了Telon类染料及匀染剂Levegal FTS,分析了Telon染料用量的计算方法,并通过实验得到了匀染剂Levegal FTS的最佳用量,简要说明了Telon类染料染Nylon的各项最佳染色工艺条件。

Study on Preparation and Properties of La_2O_3/MC Nylon Nanocomposites

A series of La2O3/MC nylon nanocomposites were prepared via in situ polymerization. The effects of content of nano-La2O3 on the mechanical properties of nanocomposites were studied. Dispersion of nano-La2O3 in MC nylon matrix was observed with SEM. The crystal structure of nanocomposites was characterized by means of XRD. SEM analysis shows that La2O3 nanoparticles are uniformly dispersed in MC nylon matrix and little clustering exists when the content of nano- La2O3 is lower than 1%, however, when the content of nano-La2O3 is more than 1%, it begins to cluster. XRD analysis indicats that nano-La2O3 does not change the crystal structure of MC nylon. Mechanical properties tests show that the tensile strength, elongation at break, impact strength, flexural strength, and flexural modulus of nanocomposites first increase then decrease as the content of nano-La2O3 is increased. When the content of nano-La2O3 is 0.5%, the tensile strength and elongation at break of nanocomposites reach maximum, which are 17.9% and 52.1% higher respectively than those of MC nylon. When the content of nano-La2O3 is 1.0%, the impact strength, flexural strength and flexural modulus of nanocomposites reach maximum, which are 36.6 %, 12.7 % and 16.3 % higher respectively than those of MC nylon.

Isothermal and nonisothermal crystallization kinetics of bio-sourced nylon 69

Bio-sourced nylon 69,one of promising engineering plastics,has a great potential in developing sustainable technology and various commercial applications.Isothermal and nonisothermal crystallization kinetics of nylon 69 is a base to optimize the process conditions and establish the structure–property correlations for nylon 69,and it is also highly bene ficial for successful applications of nylon products in industry.Isothermal and nonisothermal crystallization kinetics has been investigated by differential scanning calorimetry for nylon 69,bio-sourced even–odd nylon.The isothermal crystallization kinetics has been analyzed by the Avrami equation,the calculated Avrami exponent at various crystallization temperatures falls into the range of 2.28 and 2.86.In addition,the Avrami equation modi fied by Jeziorny and the equation suggested by Mo have been adopted to study the nonisothermal crystallization.The activation energies for isothermal and nonisothermal crystallization have also been determined.The study demonstrates that the crystallization model of nylon 69 might be a twodimensional(circular)growth at both isothermal and nonisothermal crystallization conditions.Furthermore,the value of the crystallization rate parameter(K)decreases signi ficantly but the crystallization half-time(t1/2)increases with the increase of the isothermal crystallization temperature.To nonisothermal crystallization,the crystallization rate increases as the cooling rate increases according to the analysis of Jeziorny's theory.The results of Mo's theory suggest that a faster cooling rate is required to reach a higher relative degree of crystallinity in a unit of time,and crystallization rate decreases when the relative degree of crystallinity increases at nonisothermal crystallization conditions.

Tribological Behavior of MC Nylon6 Composites Filled with Glass Fiber and Flyash

To improve tribological property of MC Nylon6, the glass fiber and fly ash reinforced monomer casting nylon compogites （GFFAPA） were prepared by anionic polymerization of e-caprolactam. The friction and wear behaviors of composites under dry condition, water lubrication and oil lubrication were investigated through a ring-black wear tester. Worn surfaces were analyzed using a scanning electron microscope. The experimental results show that the tensile strength and hardness of nylon composites are obviously improved with reinforcement increasing. Compared to MC nylon, the lowest friction coefficient and wear rate of glass fiber reinforced nylon composites （GFPA） with GF30% respectively decrease by 33.1% and 65.3%, of fly ash reinforced nylon composites （FAPA） with FA20% decrease by 5.2% and 68.9% and of GFFAPA composites with GF30% and FA10% decrease by 57.8% and 89.9%. The main wear mechanisms of FAPA composites are adhesive and abrasive wear and of GFPA composites with high proportion are abrasive and fatigue wear. The wom surfaces of GFFAPA composites are much multiplex and the optional distributing glass fiber and fly ash have a synergetic effect on the wear resistance for GFFAPA composites. Compared with dry friction, the friction coefficient and wear rate under oil lubricated conditions decrease sharply while the latter reversely increase under water lubricated conditions. The wear mechanisms under water lubricated condition are principally chemical corrosion wear and abrasive wear and they become boundary friction under oil lubricated condition.

Non-isothermal crystallization kinetics of Nylon 10T and Nylon 10T/1010 copolymers:Effect of sebacic acid as a third comonomer

Nylon 10 T and Nylon 10T/1010 samples were synthesized by direct melt polymerization. The non-isothermal crystallization kinetics of Nylon 10 T and Nylon 10T/1010 was investigated by means of differential scanning calorimetry(DSC). Jeziorny equation and Mo equation were applied to describe the non-isothermal crystallization kinetics of the Nylon 10 T and the Nylon 10T/1010. The activation energies for non-isothermal crystallization were obtained by Vyazovkin's method and Friedman's method, respectively. These results showed that Jeziorny equation and Mo equation well described the non-isothermal crystallization kinetics of the Nylon 10 T and the Nylon 10T/1010. It was found that the values of the activation energy for non-isothermal crystallization of the Nylon 10T/1010 were lower than those of the Nylon 10 T at a given temperature or relative crystallinity degree,which revealed that crystallization ability of the Nylon 10T/1010 was higher. The crystal morphology was observed by means of a polarized optical microscope(POM) and X-ray diffraction(XRD). It was found that the addition of sebacic acid comonomer not only did not change the crystal form of the Nylon 10 T, but also significantly increased the number and decreased the size of spherulites. Comparing with the Nylon 10 T, the crystallization rate was increased with the addition of the sebacic acid comonomer.

THE EFFECT OF BLENDING SEQUENCE ON PHASE MORPHOLOGY OF NYLON 6/ABS/SMA BLENDS

The preparation process-dependent phase morphology of blends composed of nylon 6 and acrylonitrile-butadiene- styrene(ABS)over a composition range of 30-70 wt% using a styrene-maleic anhydride(SMA)copolymer as the compatibilizing agent with a constant content(5phr)was investigated.The results of the scanning electron microscope (SEM)observation revealed that compared with the binary blends of nylon 6 and ABS,the existence of SMA caused a composition shift of phase inversion to a higher weight fraction of ny...

FRACTAL BEHAVIOR OF DEVELOPMENT OF PHASE SEPARATION AND CRYSTALLIZATION IN BLENDS OF NYLON-6 WITH SODIUM SALT OF ETHYLENE /METHACRYLIC ACID COPOLYMER

Phase separation was studied by the optical microscopy in blends of nylon 6 (PA6) with sodium salt of ethylene/methacrylic acid copolymer (PEMA).The image collecting technology was used to keep track of the development of blends at a certain temperature.The fractal dimension of phase separation was calculated by the image solving technology according to the fractal theory and the self similarity behavior of the process was proved.The relationship of the fractal behavior with composition and experimental temperature was discussed.The fractal behavior of the crystallization development of the crystal phase of PA6 in blends was also discussed and the fractal behavior calculated.

MELTING CRYSTALLIZATION BEHAVIOR OF NYLON 66

Analysis of isothermal and nonisothermal crystallization kinetics of nylon 66 was carried out using differential scanning calorimetry (DSC). The commonly used Avrami equation and that modified by Jeziorny were used, respectively, to fit the primary stage of isothermal and nonisothermal crystallizations of nylon 66. In the isothermal crystallization process, mechanisms of spherulitic nucleation and growth were discussed. The lateral and folding surface free energies determined from the Lauritzen-Hoffman treatment are sigma = 9.77 erg/cm(2) and sigma (e) = 155.48 erg/cm(2), respectively; and the work of chain folding is q = 33.14 kJ/mol. The nonisothermal crystallization kinetics of nylon 66 was analyzed by using the Mo method combined with the Avrami and Ozawa equations. The average Avrami exponent (n) over bar was determined to be 3.45. The activation energies (DeltaE) were determined to be -485.45 kJ/mol and -331.27 kJ/mol, respectively, for the isothermal and nonisothermal crystallization processes by the Arrhenius and the Kissinger methods.

Multi-objective optimization and experiment of nylon cord rubber in expandable packer

Nylon cord rubber has the advantages of small residual deformation and is easy to lift and lower the tubing string in low-permeability oil and gas reservoirs.However,it is associated with low-pressure resistance and poor sealing performance.To enhance the performance of nylon cord rubber,a three-dimensional numerical model of the nylon cord rubber was established and its accuracy experimentally determined.The Plackett-Burman test,the Steepest climbing test and the Response surface method were used to acquire the polynomial response surface model connecting structural parameters with bearing and sealing pressure.Using genetic algorithms,optimal structural parameters of nylon cord rubber were determined depending on field operation.The reliability of the optimized results was verified by laboratory tests.It was shown that after optimization,the bearing capacity of the expandable packer increased by 25%while the sealing performance increased by 66%.In addition,the bearing pressure was 70 MPa while the sealing pressure was 50 MPa.These measurements effectively met the on-site requirements of high-pressure and fine fracturing in low-permeability oil and gas reservoirs.

MULTIPLE MELTING AND CRYSTALLIZATION BEHAVIOR OF NYLON 1212

The wide-angle X-ray diffraction （WAXD） patterns of isothermally crystallized Nylon 1212 show that γ-form crystals form below 90℃ and the α-form crystals can exist above 140℃. In the temperature range of 90-140℃, the α-form and γ-form crystals coexist. Variable-temperature WAXD exhibits that the nylon 1212 γ-form does not show crystal transition on heating, while α-form isothermally crystallized at 160℃ exhibits Brill transition at a little higher than 180℃ on heating. The multiple melting behaviors of Nylon 1212 isothermally crystallized from melt come from a complex mechanism of different crystal structures, dual lamellar population and melting-recrystallization. In polarized optical microscope （POM） observations, Nylon 1212 isothermally crystallized at 175℃ shows the ringed banded spherulites. However, at temperatures below 160℃ the ringed banded image disappears, and cross-extinct spherulites are formed.

STRUCTURAL PHASE TRANSITION OF ALIPHATIC NYLONS VIEWED FROM THE WAXD/SAXS AND VIBRATIONAL SPECTRAL MEASUREMENTS AND MOLECULAR DYNAMICS CALCULATION

The crystalline phase transition of aliphatic nylon 10/10 has been investigated on the basis of the simultaneous measurement of wide-angle and small-angle X-ray scatterings, the infrared spectral measurement and the molecular dynamics calculation. An interpretation of infrared spectra taken for a series of nylon samples and the corresponding model compounds was successfully made, allowing us to assign the infrared bands of the planar-zigzag methylene segments reasonably. As a result the methylene segmental parts of molecular chains were found to experience an order-to-disorder transition in the Brill transition region, where the intermolecular hydrogen bonds are kept alive although the bond strength becomes weaker at higher temperature. The small-angle X-ray scattering data revealed a slight change in lamellar stacking mode in the transition region. The crystal structure has been found to change more remarkably in the temperature region immediately below the melting point, where the conformationally disordered chains experienced drastic rotational and translational motions without any constraints by hydrogen bonds, and the lamellar thickness increased largely along the chain axis. These experimental results were reasonably reproduced by the molecular dynamics calculation performed at the various temperatures.

Isothermal Crystallization Kinetics of Nylon 10T and Nylon 10T/1010 Copolymers:Effect of Sebacic Acid as a Third Comonomer

Nylon 10T and nylon 10T/1010 samples were synthesized by direct melt polymerization.The isothermal crystallization kinetics of nylon 10T and nylon 10T/1010 was investigated by means of differential scanning calorimetry（DSC）.The crystallization kinetics under isothermal condition has been analyzed by the Avrami equation.It was found that the Avrami equation was well-suited to describe the isothermal crystallization kinetics,combined with the results of the Turnbull-Fisher equation.The values of Tm^0 and Kg were obtained by Hoffman-Weeks and Lauritzen-Hoffman equations,respectively.The activation energies for isothermal crystallization of nylon 10T and nylon 10T/1010 were determined using the Arrhenius equation and found to be-123.24 and-81.86 kJ·mol^（-1）,respectively,which reveals that the crystallization ability of nylon 10T/1010was lower than that of nylon 10T during the isothermal crystallization process.The crystal morphology was observed by means of polarized optical microscopy（POM）and X-ray diffraction（XRD）.It was found that the addition of sebacic acid comonomer did not change the crystal form of nylon 10T,but significantly increased the number and decreased the size of spherulites.

Comparison of wear behavior of ABS and Nylon6-Fe powder composite parts prepared with fused deposition modelling

Fused deposition modeling(FDM) is one of the latest rapid prototyping techniques in which parts can be manufactured at a fast pace and are manufactured with a high accuracy. This research work is carried out to study the friction and wear behavior of parts made of newly developed Nylon6-Fe composite material by FDM. This work also involves the comparison of the friction and wear characteristics of the Nylon6-Fe composite with the existing acrylonitrile butadiene styrene(ABS) filament of the FDM machine. This Is carried out on the pin on disk setup by varying the load(5, 10, 15 and 20 N) and speed(200 and 300 r/min). It is concluded that the newly developed composite is highly wear resistant and can be used in industrial applications where wear resistance is of paramount importance. Morphology of the surface in contact with the Nylon6-Fe composite and ABS is also carried out.