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1.
In this article, a series of amphiphilic graft copolymers, namely poly(higher α‐olefin‐copara‐methylstyrene)‐graft‐poly(ethylene glycol), and poly(higher α‐olefin‐co‐acrylic acid)‐graft‐poly(ethylene glycol) was used as modifying agent to increase the wettability of the surface of linear low‐density polyethylene (LLDPE) film. The wettability of the surface of LLDPE film could be increased effectively by spin coating of the amphiphilic graft copolymers onto the surface of LLDPE film. The higher the content of poly(ethylene glycol) (PEG) segments, the lower the water contact angle was. The water contact angle of modified LLDPE films was reduced as low as 25°. However, the adhesion between the amphiphilic graft copolymer and LLDPE film was poor. To solve this problem, the modified LLDPE films coated by the amphiphilic graft copolymers were annealed at 110° for 12 h. During the period of annealing, heating made polymer chain move and rearrange quickly. When the film was cooled down, the alkyl group of higher α‐olefin units and LLDPE began to entangle and crystallize. Driven by crystallization, the PEG segments rearranged and enriched in the interface between the amphiphilic graft copolymer and air. By this surface modification method, the amphiphilic graft copolymer was fixed on the surface of LLDPE film. And the water contact angle was further reduced as low as 14.8°. The experimental results of this article demonstrate the potential pathway to provide an effective and durable anti‐fog LLDPE film. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

2.
In this article, we report that thermoresponsive poly(N‐isopropyl acrylamide) (PNIPAAm) was successfully grafted onto a cotton fabric (CF) surface by free‐radical solution grafting polymerization; we obtained a thermoresponsive CF‐grafted PNIPAAm. This reaction system only contained four constituents: the monomer, solvent, initiator, and CFs. Ammonium peroxydisulfate was chosen as the initiator, and water was chosen as the solvent. A series of initiator concentrations and grafting polymerization temperatures were used in the experiments, and their effects on the grafting ratio (G) were also studied. Also, the effects of the G of CF‐g‐PNIPAAm on their corresponding thermoresponses was studied further. The structure of CF‐g‐PNIPAAm was characterized by Fourier transform infrared spectroscopy–attenuated total reflectance analysis and scanning electron microscopy analysis. The G of CF‐g‐PNIPAAm was measured by a gravimetric method. The thermoresponse of CF‐g‐PNIPAAm was characterized by modulated differential scanning calorimetry, water contact angle measurements, and wetting time measurements. The experiments manifested the following results: (1) the initiator concentration and grafting polymerization temperature both influenced G, (2) the grafted PNIPAAm covered the CF surface, (3) the CF‐g‐PNIPAAm showed thermoresponsive hydrophilicity/hydrophobicity, and (4) a relationship existed between the thermoresponse of CF‐g‐PNIPAAm and the corresponding G. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41193.  相似文献   

3.
Synthesis of fluorine containing polypropylene (PP F) from chlorinated polypropylene (PP Cl) via Cu(I) catalyzed Huisgen type 1,3-dipolar cycloaddition (CuAAC) and its water repellency properties are demonstrated. Initially, clickable azido-functional polypropylene (PP N3) and alkyne-functionalized fluorine compound (F Al) are independently prepared by nucleophilic substitution of PP Cl with azidotrimethylsilane-tetrabutylammonium fluoride and esterification reactions of 2,2,3,3,4,4,5,5-octafluoro-1-pentanol with 4-pentyonic acid. The CuAAC reaction between PP N3 and F Al leads to corresponding PP F under mild conditions. The chemical structures and surface properties of desired PP F are characterized by Fourier transform infrared, 1H-NMR, differential scanning calorimetry, scanning electron microscopy, atomic force microscope, and contact angle analyses. Based on water contact angle (WCA) measurement, it is found that both PP Cl and PP N3 films have shown similar hydrophobicity, whereas the WCA of PP F is surprisingly decreased due to the presence of ester and triazole groups coming from F Al compound and the clicked product. This facile modification procedure could be utilized in order to alter the wetting or thermal properties of the commercial polymers for potential applications. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47072.  相似文献   

4.
Chitosan coating of polyethylene (PE) was proposed as a new procedure to improve its biocompatibility and surface properties. The functionalization of the PE film surface by covalent bonding of chitosan coating and its effect on the surface mechanical properties, as surface elasticity, stiffness, and adhesion (that are important in different biological processes) were investigated by nano‐indentation, scratch, and atomic force microscopy. It has been established that chitosan grafting onto corona functionalized PE surface using various coupling agents significantly improves the surface hardness and elastic modulus although they decrease in depth of the layer. Compared to the neat PE substrate, the chitosan coated samples show significant improved friction properties and tear resistance. The surface roughness features correlate with the micro‐mechanical parameters. Therefore, the covalent immobilization of the chitosan onto PE leads to a stable coating with better mechanical performance being recommended as a promising material for medical applications and food packaging. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42344.  相似文献   

5.
Amino‐functinonalized carbon fibers were achieved via electron‐beam (EB) irradiation in Diethylenetriamine (DETA) solution and triethylene tetramine (TETA) solution at 200 kGy. Different graft monomer concentrations were investigated to find the optimal concentration of each graft monomer. X‐ray photoelectron spectroscopy, scanning electron microscopy, and Raman spectroscopy were applied to investigate chemical composition and functional groups, topography and disorder degree of amino‐functionalized carbon fibers surface. Meanwhile, adsorption ability and interfacial adhesion between modified carbon fibers and epoxy resin were determined by TGA and interlaminar shear strength (ILSS). It is found that amino‐functionalized carbon fibers which had rougher and more active surface performed better adsorption ability on epoxy resin than untreated fibers. The optimal ILSS values of carbon fiber (treated with DETA and TETA) reinforced composites were 21.37 MPa and 18.28 MPa, which were much higher than that of untreated fiber reinforced composites. The comprehensive results demonstrated that in this condition, the optimal grafting concentrations of both DETA and TETA were 1.5 mol/L. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40274.  相似文献   

6.
Hybrid organic‐inorganic coatings can be extremely beneficial to improve the performance of steel substrates as their outstanding adhesion strength, scratch resistance, and chemical endurance. However, the design and manufacture of the appropriate coating systems on the different metal alloys can be troublesome. Defective coatings can cause the deterioration of their performance, especially the resistance to aggressive chemicals. In this work, the deposition of functionalized methyl phenyl polysiloxane resins on hot rolled and high strength Fe 430 B steel substrates with and without an intermediate layer of a hybrid organic‐inorganic grafting polymer (vinyltriethoxysilane) is comparatively evaluated. Visual appearance, scratch and wear resistance of the coatings as well as their attitude to act as chemical proof barriers are investigated. Proper functionalization of methyl phenyl polysiloxane resins with hydroxyl and alkoxy groups can lead to coatings that are well adhered to the underlying substrates, thus exploiting all the performance they were designed for. In this case, the use of an organo‐silane interlayer can further increment the final properties of the overall coating systems. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40624.  相似文献   

7.
A novel macromonomer containing fluorinated units (PHFBMA‐GMA) was synthesized through a two‐step procedure: firstly, hexafluoro‐butyl methacrylate (HFBMA) was polymerized in the presence of functional chain transfer agent 3‐mercaptopropionic acid (MPA) and then the carboxyl acid group terminated polymer was end‐capped with glycidyl methacrylate (GMA). Chemical structures of PHFBMA‐GMA were characterized by gel permeation chromatography, fourier transform infrared spectroscopy (FTIR), and 1H nuclear magnetic resonance (NMR). Subsequently, PHFBMA‐GMA was employed as reactive surface additives added into UV‐cured polyacrylate to modify UV‐curable coatings. It is convenient to control the tail length of the fluorinated segments in this study by adjusting the ratio of initiator and chain transfer agent. The influence of both the concentration and the molecular weight of PHFBMA‐GMA on the surface properties of UV‐cured films was investigated. With increasing both the concentration and the molecular weight of PHFBMA‐GMA, the surface energy of the UV‐cured films decreased. X‐ray photoelectron spectroscopy was employed to characterize and quantify the surface composition and the results confirm the enrichment of fluorinate atoms on the surface. Moreover, the physical properties of UV‐cured films, such as gel content, water absorption, pencil hardness, adhesion, chemical resistance, mechanical properties, optical transmittance, and thermal properties, were also investigated in detail. The novel macromonomer was economical but effective to modify the properties of the UV‐curable coatings. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43116.  相似文献   

8.
In this study, methacrylic acid (MAA) and acrylic acid (AA) were photografted onto the ultrahigh molecular weight polyethylene (UHMWPE) plates at different monomer concentrations and temperatures, and the grafted UHMWPE plates were bonded with aqueous polyvinyl alcohol (PVA) solutions. The tensile shear adhesive strength of both grafted UHMWPE plates was also discussed in relation to wettability and water absorptivity. The location of failure was also estimated by X‐ray photoelectron spectroscopy (XPS). Wettability of the MAA‐grafted UHMWPE plates became constant, when the UHMWPE surface was fully covered with grafted PMAA chains. Conversely, wettability of the AA‐grafted UHMWPE plates passed through the maximum value and then gradually decreased against the grafted amount probably due to aggregation of grafted PAA chains. Water absorptivity of the grafted layers formed at lower monomer concentrations or temperatures sharply increased at lower grafted amounts. The adhesive strength increased with the grafted amount and substrate breaking was observed at higher grafted amounts, indicating that a main factor to increase the adhesive strength is the formation of a grafted layer by shorter grafted polymer chains and/or the restriction of the location of photografting to the outer surface region. In addition, surface analysis by XPS showed that failure occurred in the boundary between the layer composed of grafted polymer chains and PVA chains and the ungrafted layer at a low adhesive strength, and the location of failure was shifted to the grafted layer containing PVA chains at the grafted amount increased. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40133.  相似文献   

9.
On the basis of the short‐chained modifier of stearyl‐alcohol poly(ethylene oxide) ether (AEO), an entrapping modification was carried out on the polypropylene (PP) surface for hydrophilic improvement. A swelling layer was confirmed locating in the amorphous region on the PP surface, from which the modifiers could penetrate into the surface. The AEO‐8 modifier achieved the optimal hydrophilic modification on the surface with a contact angle of 20.6° and modifier coverage of 19.2%. A microphase separation was speculated to occur between the poly(ethylene oxide) (PEO) chain of AEO and the PP substrate in the entrapping surface, after which surface‐enriched PEO chains could improve surface hydrophilicity, simultaneously, reserved stearyl chains in the surface could approach modifier fixation. Water immersion durability of the modified surface could be improved by establishing a covalent linkage in the surface‐fixed structure. This work gives more comprehensive insights in the entrapping modification on the semi‐crystalline PP surface based on the short‐chained and block modifier. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43607.  相似文献   

10.
This article reports a study of some functionalized polyolefins evaluated as compatibilizers in polyethylene nanocomposites. The functionalized polymers were prepared by direct metallocene‐mediated copolymerizations of ethylene and a functional comonomer. The prepared nanocomposites were evaluated for mechanical and barrier property enhancement. A good combination of mechanical and barrier properties was obtained with the metallocene‐based functionalized polyethylene. The toughness–stiffness balance was better than or comparable to that achieved with conventional functionalized polymers such as maleic anhydride grafted polyethylene. The results also indicated that these metallocene‐based functionalized polyolefins, when used as compatibilizers, could have relatively higher molar masses and lower functionality than those of conventional post‐reactor‐modified compatibilizers, and so the drawbacks associated with the latter could be avoided. Their inherent properties could also further improve the final nanocomposite properties. This was attributed to the more homogeneous nature of metallocene‐catalyzed polymers in comparison with post‐reactor‐modified products. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 1094–1100, 2004  相似文献   

11.
The interfacial compatibility between polymers and nanoclay fillers as well as the thermostability of both components are important characteristics for processing them into polymer composites. While the polymer component is often grafted using common polymerization reactions, the nanoclay component is usually surface modified by surfactant treatment to improve compatibility. In the present study, the polymer ethylene vinyl alcohol and a nanoclay filler based on natural bentonite are both surface modified by different silanes, 3‐glycidoxypropyltrimethoxysilane and methacryloxymethyltrimethoxysilane and their interfacial properties are investigated by inverse gas chromatography. The silane‐modified samples had improved interfacial properties as reflected by a significant increase in dispersive and specific surface energies. Lewis acidities were determined using chloroform and 1,4‐dioxane as polar probes and showed a good match between polymer and nanofiller interfaces. Lewis acidity was generally lower after silane‐modification. Silanization yielded increased thermal stability of the treated samples. Thus, silanization led to improved compatibility and enhanced thermal stability which facilitates further processing. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41227.  相似文献   

12.
In this study, a macroporous polypropylene membrane (MPPM) was grafted with hydrophilic poly(N‐vinyl‐2‐pyrrolidone) (PNVP) based on a one‐pot reversible‐addition fragmentation chain transfer (RAFT) polymerization and click chemistry. First, we prepared the clickable membrane by bromination and following SN2 nucleophilic substitution reaction; then, click chemistry and RAFT polymerization were performed in one‐pot to graft PNVP to the MPPM surface. The surface characterizations, including attenuated total reflectance/Fourier transform infrared spectroscopy, X‐ray photoelectron spectroscopy, and field‐emission scanning electron microscopy, illustrated that PNVP was really grafted onto the MPPM surface. The permeation and antifouling characteristics of the MPPMs were measured by the filtration of a bovine serum albumin dispersion; this showed that in contrast to the nascent membrane, the grafted membrane efficiently obstructed protein molecules because of the compactly grafted polymer chains. The hydrophilicity and antifouling properties of MPPM were greatly ameliorated after modification. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42649.  相似文献   

13.
Cotton fabric was successfully modified using a simple mist polymerization with polyurethane (PU) prepolymer and ethylene glycol as the monomers. Scanning electron microscope showed the presence of a very thin polymer coating on the cotton fiber surface. Martindale abrasion tests revealed that the thin PU coating imparted to the cotton fabric a doubled wearing durability compared with the original fabric. Additional experiments demonstrated that the mist polymerization has little impact on the desired cotton properties such as water absorptivity, vapor transmissibility, mechanical property, and flexibility. Considering the excellent balance between the enhanced abrasion resistance and the cotton natures, this surface modification methodology has potential to fabricate wearing durable textiles. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43024.  相似文献   

14.
A (meth)acrylate copolymer grafted with long fluorinated side chains (AGLF) was synthesized successfully through a two‐step procedure. First, a carboxyl terminated fluoropolymer, poly(2,2,3,4,4,4‐hexafluorobutyl methacrylate) was synthesized by conventional radical polymerization in the presence of 3‐mercaptopropionic acid as chain transfer agent. And then the fluoropolymer was grafted to the in‐house synthesized polyacrylate (MMA‐r‐BA‐r‐GMA). Fourier transform infrared spectroscopy and 1H‐nuclear magnetic resonance spectroscopy were employed to verify the synthesis of AGLF. Moreover, the surface properties were investigated by contact angle measurement and X‐ray photoelectron spectroscopy. The results proved that a small amount of poly(2,2,3,4,4,4‐hexafluorobutyl methacrylate) addition can create a hydrophobic surface effectively. Furthermore, the X‐ray photoelectron spectroscopy results showed that it is the AGLF grafted with longer fluorinated side chain that have more fluorine atoms enriched on the surface and thus performed better hydrophobicity and lipophobicity. Testified by thermogravimetric analysis and differential scanning calorimetry, it was found that AGLF films have excellent thermal properties. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 45894.  相似文献   

15.
Pyrene end‐labeled star poly(?‐caprolactone)s (PCLs) with polyhedral oligomeric silsesquioxane (POSS) core were prepared by combination of copper(I)‐catalyzed azide–alkyne cycloaddition (CuAAC) click chemistry and ring‐opening polymerization techniques. First, ?‐caprolactone (?‐CL) is polymerized by using 1‐pyrene methanol as initiator and stannous octoate as catalyst to obtain α‐pyrene‐ω‐hydroxyl telechelic PCL with different chain lengths. Then, its hydroxyl group is converted to acetylene functionality by esterification reaction with propargyl chloroformate. Finally, the CuAAC click reaction of α‐pyrene‐ω‐acetylene telechelic PCL with POSS‐(N3)8 leads to corresponding pyrene end‐labeled star‐shaped PCLs. The successful synthesis of pyrene end‐labeled star polymers is clearly confirmed by 1H‐nuclear magnetic resonance, Fourier transform infrared, gel permeation chromatograph, differential scanning calorimeter, and thermogravimetric analysis. Furthermore, non‐covalent interactions of obtained star polymers with fullerene are investigated in liquid media. Based on Raman spectroscopy and visual investigations, the star polymer having shorter chain length exhibited better and more stable dispersion with fullerene. The amount of pyrene units present per polymer chains can directly influence the dispersion stability of fullerene. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46520.  相似文献   

16.
An N‐halamine monomer, 3‐allyl‐5,5‐dimethylhydantoin (ADMH), was synthesized by a Gabriel reaction of 5,5‐dimethylhydantoin and 3‐bromopropene. Antimicrobial coatings of poly[1‐(4,4‐dimethyl‐2,5‐dioxoimidazolidin‐1‐methyl)ethylene] were prepared on plasma‐treated PET fabrics via a vapor‐phase assisted polymerization (VAP) process using gasified ADMH as monomer. The coatings endow the PET fabrics with an antimicrobial efficiency greater than 80% for both Escherichia coli and Staphylococcus aureus after chlorination of the N‐halamine polymer with dilute bleach solution. The obtained antimicrobial effect has remarkable durability that can bear over 30 times of stringent laundering tests. Compared with other antimicrobial finishing methods, the VAP methodology offers great advantages in needless of organic solvents and small consumption of monomer. It has potential applications in a wide variety of fields such as hygienic clothing, underwear, socks, and medical textiles. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41824.  相似文献   

17.
The influence of the surface chemical modification on the bulk behavior of epoxy based networks has been studied. In particular, the bulk dynamics of epoxy‐amine networks modified with fluorinated side chains has been characterized by means of broadband dielectric spectroscopy (BDS), differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR) spectroscopy. The fluorination effect on the structure and dynamics of the materials has been related with the observed changes in both segmental and secondary relaxations. An acceleration of the segmental dynamics as the fluorination degree increases has been clearly observed. As a result, a compromise between fluorine surface enrichment and bulk modification has been proposed for these materials. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42690.  相似文献   

18.
Polymer‐cyclodextrin (CD) composite nanofibers, by virtue of the hollow cavities and abundant hydroxyl groups present in CDs, have tremendous potential in a variety of biomedical applications. However, in most cases, especially in aliphatic polyesters, polymer chains thread readily into CD cavities, therefore its potential has not yet been fully realized. Herein, we report the formation of poly(ε‐caprolactone) (PCL)/β‐CD functional nanofibers by electrospinning their mixture from chloroform/N,N‐dimethylformamide (60 : 40). The fiber diameters of the neat PCL and β‐CD functionalized fibers were measured from the images obtained from a scanning electron microscope and were found to be about 500 nm. The efficiency of wound odor absorbance by these composite fibers was studied using a simulated wound odor solution, consisting of butyric and propionic acids in ethanol. Immersion tests indicated that even under less than ideal test conditions, the nanofibers containing β‐CDs were very efficient in masking the odor. The odor masking capability of the β‐CD functionalized PCL nanofibers were further confirmed by thermogravimetric analyses and GC observations, with the former method showing unique degradation patterns. The PCL/β‐CD nanocomposites, by virtue of having their β‐CD cavities free and unthreaded by PCL, could potentially be an ideal substrate for removing wound odors through formation of inclusion compounds with odorants, while providing an ideal environment for the wound to heal. These results suggest tailoring polymer‐CD nanostructures for specific applications in wound odor absorbance, surface grafting of chemical moieties, and vehicles for drug delivery, as examples. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42782.  相似文献   

19.
The blending of a block copolymer into the membrane matrix is a convenient and efficient way to modify membranes. In this study, high‐density polyethylene/polyethylene‐b‐poly(ethylene glycol) (PEG) membranes were prepared via a thermally induced phase separation process, and the extractant effect was investigated. An interesting finding was that the nonpolar extractant (n‐hexane) was more conducive to the surface enrichment of the PEG chains than the polar solvent (ethanol). The reason was deemed to be the combined effect of the entropy drive, interfacial energy, and swelling behavior. In addition, the membrane performance related to the surface chemical properties was studied. The results suggest that the prepared blend membranes extracted by n‐hexane showed enhanced the hydrophilicity, antifouling properties, and water flux. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3816–3824, 2013  相似文献   

20.
In this work, poly(ethylene glcycol)‐grafted chitosan (PEG‐g‐CS) was synthesized by conjugating PEG to the chitosan (CS) backbone. Such PEGylated CS copolymer was further characterized by FTIR and 1H NMR, and the results demonstrated the successful synthesis. After PEGylation, the water solubility of CS was significantly improved due to the hydrophilicity of the PEG polymer. Therefore, this PEGylated CS was prepared as water borne coating for leather surface. The morphology and hydrophilicity of this coating on leather was studied by SEM and water contact angle measurement. Furthermore, the antimicrobial activity of PEGylated CS coating was investigated by measuring its minimum inhibitory concentration and the inhibition zone of coated leather against Gram‐negative Escherichia coli and Gram‐positive Staphylococcus aureus, respectively. Compared to CS coating, such PEG‐g‐CS coating exhibited better antimicrobial property, which indicated the synergetic effect of the antimicrobial property of CS and the antiadhesive property of PEG. Thus, this PEGylated CS copolymer can be used as efficiently antimicrobial coating for leather product. © 2016 The Authors Journal of Applied Polymer Science Published by Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43465.  相似文献   

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