A New Modified Method to Obtain a High Melt Index of PLA Polymer and Preparation of Melt-Blown Nonwoven Cloth

Qian Lin,Jianyong Feng,Lixia Zhao 한국섬유공학회 2023 Fibers and polymers Vol.24 No.10

Due to the low melt index of polylactic acid (PLA) polymer, it is difficult to melt-blown processing. Here, a new modified method to obtain a high melt index of PLA polymer and melt-blown nonwoven cloth was studied. PLA polymers are modified by the thermally degraded method of stannous octoate (Sn(Oct)2) and polyethylene glycol (PEG) to obtain a high melt index (1054 g/10 min) in comparison with a low melt index (23 g/10 min) of original unmodified PLA polymer. The fiber of modified PLA polymer melt-blown cloth is obviously thinner, having sub-micron fibers, the smallest fiber is about 200 nm. From our test, modified PLA polymer melt-blown cloth has good oil absorption, oil–water separation, and potential air filtration property. In terms of degradation, the modified PLA polymer melt-blown cloth showed excellent degradation performance in basic aqueous solutions at 55 °C at pH 12, reaching a degradation rate of around 95% at 60 h.

Optimization of Processing Parameters for Particle Filtration Efficiency of Polypropylene Melt-blown Fabric

Taijun Jiang,Guangsheng Zeng,Can Hu,Cong Meng,Yi Chen 한국섬유공학회 2021 Fibers and polymers Vol.22 No.4

Polypropylene melt-blown fabric as the core filter materials plays an important role in manufacturing civil andmedical epidemic prevention products. The aim of this study was to optimize and control the particle filtration efficiency andapparent surface quality of the melt-blown fabric from the perspectives of electret masterbatch composition and processingparameters. Magnesium stearate and fumed silica were used as the electret to manufacture polypropylene melt-blown fabric. The layout and charge voltage of the electret device was taken as the variables to optimize and improve the particle filtrationefficiency and bulkiness coefficient of the fabric. The temperature of the barrel and die was controlled to enhance the surfacequality and corresponding particle filtration efficiency. The results showed that a combination of organic magnesium stearateand inorganic fumed silica could obtain a balance between particle filtration efficiency and smooth processing without beingjammed. Increasing the charge voltage and rearranging the position of the charge wires could significantly enhance theparticle filtration efficiency. A better particle filtration efficiency and reasonable bulkiness coefficient could be obtained bycontrolling the diameter of the filaments by regulating the temperature of the barrel and die as well as the suction intensity. The results obtained from this study can offer valuable references in optimization of electret master batch formulation andprocessing parameters for melt-blown fabric production with different resin.

멜트블로운 폴리프로필렌/실리카 에어로겔 부직포의 제조와 단열 특성 분석

신정우,정영규,Shin, Jung Woo,Jeong, Young Gyu 한국섬유공학회 2018 한국섬유공학회지 Vol.55 No.6

To develop heat insulation fabrics with lightweight, low volume and excellent thermal insulation properties, in this study, a binder-free polypropylene/silica aerogel nonwoven fabric with an area density of ${\sim}79.7g/m^2$ was fabricated via a facile melt-blowing process, and its structure, thermal conductivity and thermal insulation properties were investigated. For comparison, a polyester hollow fiber nonwoven having a similar area density of ${\sim}84.6g/m^2$ was prepared by needle-punching. Additionally, a series of composite nonwoven fabrics was prepared by layering the melt-blown polypropylene/silica aerogel nonwoven and the polyester hollow fiber nonwoven in various combinations, and their thermal insulation properties and thermal conductivity were analyzed. Scanning electron microscopic analyses revealed that 5 wt% silica aerogel added during the melt-blown process was adhered well to polypropylene fiber surfaces of the nonwoven fabric. As a result, the melt-blown polypropylene/silica aerogel nonwoven fabric exhibited a low thermal conductivity of $43mW/m{\cdot}K$ and relatively high level of thermal insulation performance, although its thickness (~1.5 mm) was lower than that (~2.2 mm) of needle-punched polyester hollow fiber nonwoven with a similar area density. The thermal conductivity was lowered and thermal insulation performance was improved, as the melt-blown polypropylene/silica aerogel nonwoven fabric was layered. It was also found that increasing the number of melt-blown polypropylene/silica aerogel nonwoven fabric layers in the composite nonwoven fabrics layered in various combinations decreased the thermal conductivity and improved the thermal insulating properties.

멜트블로운 부직포를 이용한 전열교환소자의 특성 연구 (II) -폴리프로필렌과 나일론 멜트블로운 부직포 특성 고찰-

이창환,이종현,권은희,이경주,손은종,김성훈,Lee, Chang-Hwan,Lee, Jong-Hyun,Kwon, Eun-Hee,Lee, Kyung-Ju,Son, Eun-Jong,Kim, Seong-Hun 한국섬유공학회 2010 한국섬유공학회지 Vol.47 No.6

An enthalpy exchanger made from meltblown was prepared by a range of physical treatments to identify the production potential, and its characteristics were compared with an enthalpy exchanger based on polypropylene (PP). SEM revealed excellent compatibility between nylon and PVA. Various measurements were carried out as a function of the calendering temperature and speed, content of moisture absorbent, and concentration of water soluble polymer. The optimum conditions for the enthalpy exchanger made from nylon meltblown were as follows: a calendering temperature of $124^{\circ}C$, calendering speed of 2 m/min, and pick-up of 8~10%. The tensile strength of nylon was higher than that of the PP materials. In conclusion, nylon melt-blown nonwoven has greater potential than PP melt-blown nonwoven and can be used as a substitute in commercial paper type heat exchangers.

투습방수 성능 제어가 가능한 Vistamaxx/Polypropylene Side-by-Side 복합방사 멜트블론 부직포 특성

양병진,임기섭,Yang, Byung-Jin,Lim, Ki-Sub 한국섬유공학회 2016 한국섬유공학회지 Vol.53 No.2

Bicomponent nonwoven fabric was developed by using a melt-blown process to replace a Gore-Tex membrane with water repellency and vapor permeability in outdoor clothing. In this research, bicomponent meltblown spinning by using a S/S (side-by-side) type nozzle was used for nonwoven with a small fiber diameter, water repellency, and water vapor permeability. Vistamaxx with good adhesion was mixed with VMPP (Peroxide/PP match batch chip, Manntek Co.) as a viscosity control material to increase the melt flow index (MFI) for a small diameter of the fiber. In addition, polypropylene (PP) was used by stabilizing the viscosity of the nonwoven. In the results, the average diameter of the fiber was approximately $2.15-2.52{\mu}m$. The diameter of the fiber was decreased by increasing the melt-spinning temperature and air flow pressure. We confirmed that the water repellency was improved by increasing the fiber density in a small-diameter process.

나노 입자 첨가에 따른 정전 멜트블로운 부직포의 여과효율에 관한 연구

장선호,심현주,Jang, Sun-Ho,Shim, Hyun-Joo 한국섬유공학회 2008 한국섬유공학회지 Vol.45 No.5

We designed a filter media which could collect of submicron size particles by applying electrostatic charge. To meet our proposed design, three different types of nano-scaled materials such as nonconductor ($SiO_2$), conductor ($Al_{2}O_{3}$), ferroelectric material ($BaTiO_3$) were incorporated into the melt-blown nonwovens made of micro fiber. Polypropylene melt-blown nonwovens, basis weights of $15\;g/m^2$ and $20\;g/m^2$, were prepared. The nano particles were diffused in the ethanol and then the electro sprayed on the nonwoven fabrics to be uniformly dispersed. The specimens containing nano particles were conditioned for three hours in the vacuum drying oven. To meet our purpose, the specimens were corona charged to develop the static electricity. The charging density and filtration efficiency of the filter media were investigated with various experimental conditions: such as types of additives and their concentrations. It was shown that the charging density and filtration efficiency were increased with increasing the basis weight of the samples. The filter media incorporated with ferroelectric particles showed the most desirable results compared with the other two additives.

NMP로부터 제조된 Melt-blown흑연섬유의 안정화조건에 따른 미세구조와 전기화학적 특성

김찬,양갑승,고장면,박상희,박호철,김영민,Kim Chan,Yang Kap Seung,Ko Jang Myoun,Park Sang Hee,Park Ho Chul,Kim Young-Min 한국전기화학회 2001 한국전기화학회지 Vol.4 No.3

용융분사법으로 나프탈렌계 메조페이스 피치(mP)를 방사하여 산화안정화 속도를 변화시켜 흑연화 섬유의 모폴러지를 제어하였으며, 흑연화 섬유를 이용하여 Li-ion 이차전지 부극을 제조하여 충$\cdot$방전 거동 및 용량을 측정하였다. 용융분사조건에 따라 제조된 피치섬유의 직경은 $4{\mu}m$로부터 $16{\mu}m$까지 다양하였다 이중에서 직경 $10{\mu}m$인 피치섬유를 선택하여 세가지 승온속도 조건 $2^{\circ}C/min,\;5^{\circ}C/min,\;10^{\circ}/min$에서 산화안정화 후 $1000^{\circ}C$에서 탄소화하여 $2650^{\circ}C$에서 흑연화 한 결과, 섬유 단면이 산화안정화 조건 $2^{\circ}C/min$의 경우는 라디알 구조, $5^{\circ}C/min$의 것은 라디알-랜덤 구조, $10^{\circ}C/min$의 경우는 skin-core 구조를 형성하였고, 승온속도가 큰 경우일수록 이흑연화성이 컷다. 이것은 큰 승온속도에서는 탄소화$\cdot$흑연화 과정에서 섬유표면에서만 산화안정화가 일어나고, 내부에서는 피치분자가 유동성이 커 승온과정에서 고결정성의 흑연구조가 발달한 것으로 추측된다. 따라서 이흑연화성이 큰 $10^{\circ}C/min$에서 산화안정화 한 것이 충전방전 용량이 $2^{\circ}C/min$의 경우에 비해서 1.3배로 약 400mAh/g, 충방전 효율도 $96.8\%$로 가장 우수한 특성을 나타냈다. Naphthalene derived mesophase pitch WP) was spun into short fibers by using melt-blown technology. The pitch fibers oxidative stabilization were carried out heating rates of $2^{\circ}C/min,\;5^{\circ}C/min\;and\; 10^{\circ}/min$. The heating rate was a key factor to maximate the capacity of the Li-ion secondary battery through controlling the morphology of the graphitized fiber. The diameters of the melt-blown fibers prepared were in the range of $4{\mu}m\~16{\mu}m$ with functions of air jet speed, air temperature and the temperature of the nozzle. The graphitized fibers of $10{\mu}m$ diameters showed various morphological structure with heating rate of the stabilization. Radial, radial-random and skin-core cross-sectional structure of the fibers were observed at the respective heating rate of $2^{\circ}C/min\;5^{\circ}C/min\;and\;10^{\circ}C/min$. Most crystalline structure of graphite was obtained from the fiber stabilized at heating rate of $10^{\circ}C/min$ exhibiting the best anode performance with 400 mAh/g of capacitance and $96.8\%$ of charge/discharge efficiency.

Ba-ferrite의 분산 안정성 및 멜트블로운 PP/Ba-ferrite 부직포의 물리적 특성

최지선,이동진,Choi, Ji-Sun,Lee, Dong-Jin 한국섬유공학회 2006 한국섬유공학회지 Vol.43 No.6

The size of Ba-ferrite particles was decreased from $0.7{\mu}m\;to\;0.5{\mu}m$ by ball-milling according to SEM observation. The surface of Ba-ferrite particles was treated with stearic acid in order to improve dispersion stability in the polymer matrix. PP composites containing the surface treated Ba-ferrite particle as a magnetic particulate filler were prepared in the form of pellet from PP resin and Ba-ferrite powder by a melt compounding using a single extruder. PP/Ba-ferrite composite fabrics by a melt-blown spinning system were prepared. The relationship between the properties of PP/Ba-ferrite composite fabrics and melt-blown processing factors was investigated with these specimens. A fiber diameter and tensile strength were decreased as die to collector distance increased or as screw turning force decreased. The crystallinity was decreased with increasing Ba-ferrite content according to XRD. It was assumed that the orientation of crystalline domain in the neat PP without Ba-ferrite was increased by drawing in mechanical direction, however, the orientation in the PP composite was decreased according to XRD analysis. A coercive force, maximum magnetization and residual magnetization were increased with the screw turning force. According to the result of TGA measurement, the heat resistance was increased with the Ba-ferrite content and decreasing the die to collector distance.

Melt-blown 방사에 의한 PP/Ba-ferrite 복합 부직포 제조시의 공정인자가 부직포의 특성에 미치는 영향

한종헌 ( Jong Hun Han ),이동진 ( Dong Jin Lee ),임형미 ( Hyung Mi Lim ),이승호 ( Seung Ho Lee ),오성근 ( Sung Geoun Oh ) 한국공업화학회 2006 공업화학 Vol.17 No.3

멜트블론을 이용한 올레핀계 접착층의 특성에 관한 연구

김창훈,최세진,이현석,김한성,Kim, Chang Hun,Choi, Se Jin,Lee, Hyun Seok,Kim, Han Seong 한국섬유공학회 2016 한국섬유공학회지 Vol.53 No.2

This study investigated the interrelationships between some properties of low-density polyethylene (LDPE) web fibers produced by the melt-blown technique. Variations in the LDPE fiber's diameter and uniformity were correlated against variations in throughput pressure, hot air pressure, and nozzle temperature. The bond strength of the LDPE web adhesion layer was found to be lower than that of LDPE film. However, the LDPE web adhesion layer's air permeability was found to be significantly higher than - as much as 260 times higher - that of LDPE film. The results suggest that melt-blown LDPE web fibers are useful for producing multi-function products.