In this study,we used citric acid(CA)as a crosslinking agent,mixed with polyhexamethylene biguanide,to perform a pad-dry-cure treatment on wool fabrics to study its antimicrobial effects and physical properties.
A new class of novel polymeric crosslinging agent (NPCA), which contained silane coupling group and the epoxy groups, was designed and synthesized in our laboratory. NPCA was a non-formaldehyde multifunctional cross...A new class of novel polymeric crosslinging agent (NPCA), which contained silane coupling group and the epoxy groups, was designed and synthesized in our laboratory. NPCA was a non-formaldehyde multifunctional crosslinking polymer. The cotton fabrics dyed with 8.0% (owf) Vinylsulpone-type dyes were treated with 3.0%- 4.0% NPCA, 0.5 mol/L potassium thiocyanate as a catalyst, then padded through two dips and two nips to reach a wet pickup of 80%- 85%, then dried at 80℃ for 2 minutes and cured in oven at 140- 150℃ for 3 minutes. Crocking fastness and fixation (%) were improved with up to 1.0 -1. 5 units, 35%- 50%, respectively. And there was little difference between the color yield of dyed fabrics before and after the treatment at certain conditions. The possible crosslinking mechanism of NPCA was also investigated. It was concluded that NPCA can improve colorfastness of cotton fabric by means of the three-dimensional network, covalent bonding and other molecular forces.展开更多
A concept of potential crosslinking agent was introduced into the synthesizing process of highly oil-absorptive resin that is traditionally prepared by single chemical crosslinking.The resin was heated after manufactu...A concept of potential crosslinking agent was introduced into the synthesizing process of highly oil-absorptive resin that is traditionally prepared by single chemical crosslinking.The resin was heated after manufactured to obtain three-dimension network structure.The effects of potential crosslinking agent and the crosslinking conditions on the absorptive properties of resin were studied.The results showed that hydroxyl ethylacrylate got satisfied results,and the resin with it had good oil absorbency and oil retention.展开更多
A yellow crosslinking polymeric dye was prepared by grafting the flavone moiety containing azo chromophore onto polyvinylamine backbone.The λ max of this polymeric dye in water is 382 nm.The polymeric dye is fixed to...A yellow crosslinking polymeric dye was prepared by grafting the flavone moiety containing azo chromophore onto polyvinylamine backbone.The λ max of this polymeric dye in water is 382 nm.The polymeric dye is fixed to silk and cotton with a crosslinking agent,2-chloro-4,6-di(aminobenzene-4'-β-sulphatoethylsulphone)-1,3,5-s-triazine,which acts as a bridge between the fiber and dye molecules.The fixation of this polymeric dye reaches 99% and the dyed samples exhibit excellent rubbing and washing fastness.展开更多
Our previous studies showed that biomodification of demineralized dentin collagen with proanthocyanidin(PA) for a clinically practical duration improves the mechanical properties of the dentin matrix and the immedia...Our previous studies showed that biomodification of demineralized dentin collagen with proanthocyanidin(PA) for a clinically practical duration improves the mechanical properties of the dentin matrix and the immediate resin–dentin bond strength. The present study sought to evaluate the ability of PA biomodification to reduce collagenase-induced biodegradation of demineralized dentin matrix and dentin/adhesive interfaces in a clinically relevant manner. The effects of collagenolytic and gelatinolytic activity on PA-biomodified demineralized dentin matrix were analysed by hydroxyproline assay and gelatin zymography. Then, resin-/dentin-bonded specimens were prepared and challenged with bacterial collagenases. Dentin treated with 2% chlorhexidine and untreated dentin were used as a positive and negative control, respectively. Collagen biodegradation, the microtensile bond strengths of bonded specimens and the micromorphologies of the fractured interfaces were assessed. The results revealed that both collagenolytic and gelatinolytic activity on demineralized dentin were notably inhibited in the PA-biomodified groups, irrespective of PA concentration and biomodification duration. When challenged with exogenous collagenases, PA-biomodified bonded specimens exhibited significantly less biodegradation and maintained higher bond strengths than the untreated control. These results suggest that PA biomodification was effective at inhibiting proteolytic activity on demineralized dentin matrix and at stabilizing the adhesive/dentin interface against enzymatic degradation, is a new concept that has the potential to improve bonding durability.展开更多
Dispersion copolymerization of styrene with polyethylene glycol 200-dimethacrylae as the cross-linking agent was completed by using poly(N-vinyl pyrrolidone) and 2,2-azo-bisisobutyronitrile as the steric stabilizer ...Dispersion copolymerization of styrene with polyethylene glycol 200-dimethacrylae as the cross-linking agent was completed by using poly(N-vinyl pyrrolidone) and 2,2-azo-bisisobutyronitrile as the steric stabilizer and initiator, respectively. Crosslinked copolymeric microspheres were prepared directly by the one-step method of dispersion copolymerization. The effects of the content of polyethylene glycol 200-dimethacrylae on the particle morphology and the copolymerization rate were investigated. It shows that the crosslinking agent plays an important role in the particle morphology and the system stability. When the content of crosslinking reached 2.5wt%, the floriated particles were obtained.展开更多
Three-layer core/shell latex particles with various shell crosslinking level and shell thickness were prepared by multistep emulsion polymerization, and the hollow latex particles with different morphologies were then...Three-layer core/shell latex particles with various shell crosslinking level and shell thickness were prepared by multistep emulsion polymerization, and the hollow latex particles with different morphologies were then obtained after alkali post-treatment. Influences of divinyl benzene (DVB) content and the core/shell mass ratio on emulsion polymerization and particle morphology were investigated. Results showed that with the increase of DVB content, the percentage of total amount of --COOH on the particle surface and free in aqueous phase (PSFa) decreased, and the morphology of the post-treated particles underwent evolution from cracked, intact hollow to deficient swelling structure. Decreasing the core/shell mass ratio could not only make more carboxyl groups encapsulated by the shell, but also increase the shell resistance to the swelling of the core. The uniform hollow latex particles with intact morphology were obtained when the DVB content was 3.54 wt% and the core/shell mass ratio was 1/6.展开更多
文摘In this study,we used citric acid(CA)as a crosslinking agent,mixed with polyhexamethylene biguanide,to perform a pad-dry-cure treatment on wool fabrics to study its antimicrobial effects and physical properties.
基金Supported by the Nation Nature Science Foundation of China (No.20325210)
文摘A new class of novel polymeric crosslinging agent (NPCA), which contained silane coupling group and the epoxy groups, was designed and synthesized in our laboratory. NPCA was a non-formaldehyde multifunctional crosslinking polymer. The cotton fabrics dyed with 8.0% (owf) Vinylsulpone-type dyes were treated with 3.0%- 4.0% NPCA, 0.5 mol/L potassium thiocyanate as a catalyst, then padded through two dips and two nips to reach a wet pickup of 80%- 85%, then dried at 80℃ for 2 minutes and cured in oven at 140- 150℃ for 3 minutes. Crocking fastness and fixation (%) were improved with up to 1.0 -1. 5 units, 35%- 50%, respectively. And there was little difference between the color yield of dyed fabrics before and after the treatment at certain conditions. The possible crosslinking mechanism of NPCA was also investigated. It was concluded that NPCA can improve colorfastness of cotton fabric by means of the three-dimensional network, covalent bonding and other molecular forces.
文摘A concept of potential crosslinking agent was introduced into the synthesizing process of highly oil-absorptive resin that is traditionally prepared by single chemical crosslinking.The resin was heated after manufactured to obtain three-dimension network structure.The effects of potential crosslinking agent and the crosslinking conditions on the absorptive properties of resin were studied.The results showed that hydroxyl ethylacrylate got satisfied results,and the resin with it had good oil absorbency and oil retention.
基金Supported by the National Natural Science Foundation of China (20804007) the State Key Laboratory of Fine Chemicals(KF1014)
文摘A yellow crosslinking polymeric dye was prepared by grafting the flavone moiety containing azo chromophore onto polyvinylamine backbone.The λ max of this polymeric dye in water is 382 nm.The polymeric dye is fixed to silk and cotton with a crosslinking agent,2-chloro-4,6-di(aminobenzene-4'-β-sulphatoethylsulphone)-1,3,5-s-triazine,which acts as a bridge between the fiber and dye molecules.The fixation of this polymeric dye reaches 99% and the dyed samples exhibit excellent rubbing and washing fastness.
基金supported by research funds from the Natural Science Foundation of China (No. 81130078 and No. 81000458)Program for Changjiang Scholars and Innovative Research Team in University (No. IRT13051)
文摘Our previous studies showed that biomodification of demineralized dentin collagen with proanthocyanidin(PA) for a clinically practical duration improves the mechanical properties of the dentin matrix and the immediate resin–dentin bond strength. The present study sought to evaluate the ability of PA biomodification to reduce collagenase-induced biodegradation of demineralized dentin matrix and dentin/adhesive interfaces in a clinically relevant manner. The effects of collagenolytic and gelatinolytic activity on PA-biomodified demineralized dentin matrix were analysed by hydroxyproline assay and gelatin zymography. Then, resin-/dentin-bonded specimens were prepared and challenged with bacterial collagenases. Dentin treated with 2% chlorhexidine and untreated dentin were used as a positive and negative control, respectively. Collagen biodegradation, the microtensile bond strengths of bonded specimens and the micromorphologies of the fractured interfaces were assessed. The results revealed that both collagenolytic and gelatinolytic activity on demineralized dentin were notably inhibited in the PA-biomodified groups, irrespective of PA concentration and biomodification duration. When challenged with exogenous collagenases, PA-biomodified bonded specimens exhibited significantly less biodegradation and maintained higher bond strengths than the untreated control. These results suggest that PA biomodification was effective at inhibiting proteolytic activity on demineralized dentin matrix and at stabilizing the adhesive/dentin interface against enzymatic degradation, is a new concept that has the potential to improve bonding durability.
文摘Dispersion copolymerization of styrene with polyethylene glycol 200-dimethacrylae as the cross-linking agent was completed by using poly(N-vinyl pyrrolidone) and 2,2-azo-bisisobutyronitrile as the steric stabilizer and initiator, respectively. Crosslinked copolymeric microspheres were prepared directly by the one-step method of dispersion copolymerization. The effects of the content of polyethylene glycol 200-dimethacrylae on the particle morphology and the copolymerization rate were investigated. It shows that the crosslinking agent plays an important role in the particle morphology and the system stability. When the content of crosslinking reached 2.5wt%, the floriated particles were obtained.
文摘Three-layer core/shell latex particles with various shell crosslinking level and shell thickness were prepared by multistep emulsion polymerization, and the hollow latex particles with different morphologies were then obtained after alkali post-treatment. Influences of divinyl benzene (DVB) content and the core/shell mass ratio on emulsion polymerization and particle morphology were investigated. Results showed that with the increase of DVB content, the percentage of total amount of --COOH on the particle surface and free in aqueous phase (PSFa) decreased, and the morphology of the post-treated particles underwent evolution from cracked, intact hollow to deficient swelling structure. Decreasing the core/shell mass ratio could not only make more carboxyl groups encapsulated by the shell, but also increase the shell resistance to the swelling of the core. The uniform hollow latex particles with intact morphology were obtained when the DVB content was 3.54 wt% and the core/shell mass ratio was 1/6.