Shaohai Fu

Properties of alginate fiber spun-dyed with fluorescent pigment dispersion.

Spun-dyed alginate fiber was prepared by the spun-dyeing method with the mixture of fluorescent pigment dispersion and sodium alginate fiber spinning solution, and its properties were characterized by SEM, TGA, DSC, and XRD. The results indicate that fluorescent pigment dispersion prepared with esterified poly (styrene-alt maleic acid) had excellent compatibility with sodium alginate fiber spinning solution, and small amount of fluorescent pigment could reduce the viscosity of spun-dyed spinning solutions. SEM photo of spun-dyed alginate fiber indicated that fewer pigment particles deposited on its surface. TGA, DSC, and XRD results suggested that thermal properties and crystal phase of spun-dyed alginate fibers had slight changes compared to the original alginate fibers. The fluorescence intensity of spun-dyed alginate fiber reached its maximum when the content of fluorescent pigment was 4%. The spun-dyed alginate fiber showed excellent rubbing and washing fastness.

Regenerated cellulose fibers spun-dyed with carbon black/latex composite dispersion

A carbon black (CB)/latex composite was prepared by the method of miniemulsion polymerization for use as a colorant for spun dyeing of regenerated cellulose fibers. Analysis of experimental results revealed that the CB/latex composite had a small particle size and a narrow particle size distribution which were important to ensure a stable dispersion being later added to spinning solution. A good stability of the prepared CB/latex composite dispersion in the spinning solution indicated that it was highly possible to use the CB/latex composite as a colorant for spun dyeing of regenerated cellulose fibers. When a 3.5% mass ratio of CB/latex composite to cellulose was used for spun dyeing, the spun-dyed fibers had the highest tensile strength, breaking elongation and color strength. The rubbing and washing color fastnesses of spun-dyed regenerated cellulose fibers could satisfy requirements of most textiles. This study provided a new insight into producing spun-dyed regenerated cellulose with a novel colorant.

Advances in the Development of Antimicrobial Agents for Textiles: The Quest for Natural Products. Review

2Department of Textiles, Kwame Nkrumah University of Science and Technology Kumasi, Ghana. *Email: shaohaifu@hotmail.com Abstract The antimicrobial finishing of textiles has attracted research attention lately due to demands for a healthy lifestyle. As a result, several synthetic and natural antimicrobial agents for textiles have been developed over the years. Recently research into antimicrobials agents of natural origin have become more popular due to their enormous therapeutic potential and effectiveness in the treatment of infectious diseases while mitigating the side effects of the synthetic antimicrobials. Research into these natural biocides for textiles has seen increasing consumers awareness for two reasons, namely the potential negative impact of synthetic biocides on health versus the benefits of natural biocides, and the increasing rate of microbial resistance to most natural biocides. The immense literature on natural biocides suggests the preparedness of the research community and industry in addressing the environmental and health challenges associated with synthetic antimicrobial agents in response to the new consumer demands. This review focuses on the advances in natural antimicrobial agents and various methods of their application. Literature suggest that natural antimicrobial agents have chalked some success in terms of efficacy and wash durability, with minimal effect on the tensile strength of fabrics.

Preparation of SiO2/PSSS dispersion for formulation of white inkjet ink

SiO2 particles were prepared by sol–gel method and further modified with γ-methacryloxypropyltrimethoxysilane (KH570). A SiO2/PSSS composite was prepared with a core–shell structure, by the in situ polymerization of p-styrene sulfonate sodium (SSS) and the reaction with the KH570-modified SiO2. The SiO2/PSSS composite was optimized by adjusting the mass ratios of KH570 to SiO2, SSS to SiO2 and APS to SSS for control of the particle size and polymer layer thickness. Fourier transform infrared spectrum, contact angle and thermogravimetric analysis indicated that PSSS was successfully coated onto SiO2 particle surface. Transmission electron microscopy images showed that the prepared SiO2/PSSS dispersion had small particles and narrow particle size distribution. The white inkjet ink prepared from the SiO2/PSSS dispersion exhibited excellent thermal and centrifugal stabilities. The white inkjet ink was applied for pretreatment of fabric before colored printing which resulted in a significant enhancement of pattern brightness.

Effects of Process Conditions on Properties of Nanoscale Organic Pigment Encapsulated by Poly(styrene-maleic acid) Dispersion

The effects of process conditions on properties of nanoscale organic pigment red 122 encapsulated by poly(styrene-maleic acid) dispersion were evaluated. The results revealed that sodium hydroxide provided the dispersion superior performance as compared with other additives, regardless of it being taken as dispersant or hydrolysis reagent. An optimal process was attained by using sodium hydroxide with a dosage of 0.6–0.68 times of molar amount of ‒COOH groups in poly(styrene-maleic acid) when the pigment/poly(styrene-maleic acid) was hydrolyzed at 45°C for 30 minutes.

Rheological Properties of Nansocale Poly(Styrene-Maleic Acid) Encapsulated Organic Pigment Dispersion by Phase Separation Technique

Azo pigment yellow 14 (P.Y.14) was encapsulated into copolymer of styrene and maleic acid (PSMA) via phase separation technique followed by the preparation of composite dispersions. Herein, we mainly investigate its rheological properties. Our results showed that the apparent viscosity (n a ) of composite dispersion first decreased and then increased with an increase of molar content of maleic acid in PSMA (F M ), intrinsic viscosity of PSMA ([n]), and the weight ratio of PSMA to P.Y.14 (R C/P ), respectively. The composite dispersion with low n a was more close to Newtonian fluid when F M , [n] and R C/P were equal to 0.53, 79.65 mL/g, and 12%, respectively. n a of the composite would increase with increasing the pH value, and first decreased and then increased with a raising of the electrolyte and alcohol concentration, respectively, especially with AlCl3 and glycerol.

The Effect of pH Value on Properties of Waterborne Nanoscale Pigment and the Estimation of the Solvated Layer Thickness

Waterborne nanoscale copper phthalocyanine blue (P.B.15:3) dispersion was prepared by phase separation method. The effects of pH value on its properties were investigated and the thickness of solvated layer enclosing the pigment was estimated by the method of dynamic light scattering. The results show that the particle size first increased and then decreased with increasing pH value in the range of 1.0 to 12.0, and would be changed sharply when pH value was higher than 12.0 or lower than 1.0; the changes of the absolute Zeta potentials and the apparent viscosity were similar to that of particle size in the range of 1.0–12.0; the stability of the pigment dispersion was quite high when its pH value was in the range of 7.7–10.0. The stability, the Zeta potentials, the apparent viscosity, and the thickness of solvated layer (about 10 nm) reached their maximum at the pH value of 9.0.

Robust raspberry-like all-polymer particles for the construction of superhydrophobic surface with high water adhesive force

In this work, we present a simplified versatile approach to synthesize monodisperse and robust entirely polymeric raspberry-like particles (RPs) via an in situ seeded polymerization method. The RPs with dual-scale hierarchical structure were prepared by absorption of monomer styrene, cross-linkable monomer ethylene glycol dimethacrylate (EDGMA) and azobisisobutyronitrile (AIBN) initiator into hollow P(styrene–divinylbenzene-trifluoroethyl methacrylate) [P(S-DVB-TFEMA)] nanoreactors, and then massive corona polymeric P(S-EDGMA) particles were in situ grafted onto the core hollow P(S-DVB-TFEMA) from the inside out, obtaining the robust all-polymer P(S-DVB-TFEMA)@P(S-EDGMA) RPs. The prepared RPs possess excellent mechanical and chemical stability toward long-term ultrasonic and acid/base treatment. Without post-modifications, the particulate film assembled by the RPs exhibited the static contact angle of 154° and high adhesion to water droplets. Theoretical model of the RPs and theoretical analysis, which corresponded well to experimental data, further reveal the high adhesive phenomenon. More importantly, the prepared sticky superhydrophobic surface colored by fluorescent dye can be utilized as “a mechanical hand” for micro-droplet transportation with high visibility in UV dark chamber. Thus, we anticipate that the sticky superhydrophobic surface constructed by the robust all-polymer RPs will offer great potential applications in micro-droplet manipulation and biological detection.

Surface modification of carbon black by thiol-ene click reaction for improving dispersibility in aqueous phase

Abstract Carbon black (CB) particles were firstly encapsulated by γ-Methacryloxypropyltrimethoxysilane (MEMO) using a sol-gel method and then grafted with sodium 3-Mercapto-1-propanesulfonate (MPS) via thiol-ene click reaction. Morphology characterization reveals that modified CB particles have a core-shell structure. Element composition and chemical status derived from X-ray photoelectron spectroscopy (XPS) results prove the grafting of MPS molecules. Moreover, the crystal structure and thermal behavior of modified CB particles were characterized by Raman spectra and Thermogravimetric analysis (TGA) curves, respectively. The modified CB particles exhibit excellent self-dispersing ability in aqueous media and the dispersion has high thermal and centrifugal stability. This research provides a new insight into the preparation of inkjet printing ink with excellent stability. GRAPHICAL ABSTRACT

A Review on the Mechanism of Pigment Dispersion

ABSTRACT In the quest of ensuring successful pigment dispersion, additives are used to aid dispersion and stabilization of pigment particles through attraction forces of various chemical nature including van der waals and “liquid bridge” forces as well as anchor groups with high affinity for pigment surface. On the other hand, dispersion efficiency is significantly dependent on the effectiveness of various dispersion equipment and their energy transfer, dispersion force and effectiveness. The common denominator for all this equipment are that; dispersion is achieved by shearing forces produced by the application of high positive and negative attrition. This article reviews and explores the nature and the significance of the various methods and forces in pigment dispersion and the various stabilization mechanisms adopted in producing stably fine pigment particles, dispersion application as well as future prospects. GRAPHICAL ABSTRACT