最新刊期
卷 ， 期 1 ， 2005
- 摘要：Frontal polymerization (FP) is a mode of converting monomers into polymers via a localized reaction zone that propagates through the reaction system．The three reactants,polyether,toluene 2,4-diisocyanate and 1,4-butanediol and the catalyst (stannous caprylate) were mixed together at room temperature along with nanosilica sol and dimethylbenzene (as the solvent)．After the thermal ignition at one end of the tubular reactor and subsequent front formation,no further energy was required for polymerization to occur．The thermal front self-propagated thranghout the vessel．The effect of different molecular weights of polyether and different concentration of catalyst on frontal polymerization were investigated,along with a comparison of frontal polymerization with batch polymerization FT-IR,TEM and TGA were employed to characterize the polyurethane(PU) hybrids．The obtmned polymer materials by FP displayed similar features compared with those obtained by batch polymerization (BP) The reaction time of FP is quite less than that of BP during preparing the PU hybrids．Nanosilica sol can be well dispersed in the polyurethane hybrid matrix even though no any stirring occurs during the FP process．
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发布时间：2021-03-19
Rapid Communications
- 摘要：The copolymerization of ethylene and styrene was carried out using N catalyst activated with AIEt3 and Et2AIOAIEt2 at the present of DDS．The optimum copolymerization conditions of Al/Ti was investigated．The copolymerization products were fractionated by successive solvents extraction with boiling butanone and THF．The experimental results indicate the copolymerization products include polystyrene,ethylene-styrene copolymer,and polyethylene．The ethylene-styrene copolymers were characterized by 13C-NMR．DSC and GPC．It is found that cocatalyst not only affects copolymetization activity of N-catalyst,but also influences the ratio of different fractions in coplymerization products,especially the styrene incorporation,the melting point and the glass transition temperature of ethylene-styrene copolymer.
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发布时间：2021-03-19 - 摘要：Numerical simulation was applied to calculate temperature changes of injection molded HDPE in the cooling process．Based on the cooling model of low molecular crystalline material,the governing equations were developed to describe the cooling temperature of solid,liquid,and solid-liquid interface,respectively．An enthalpy E and a parameter T* were employed to convert the energy equation into a non-linear equation,which was then disereted by the control volume finite difference approach and solved with mathematical software Matlab．The calculated temperature profile exhibited the existence of thermosphere and phase transformation and required a time period of 2 min for the cooling cycle,which Was in agreement with the experimental data for the inner layer of the HDPE sample．Thus it can be applied to the numerical performance of Stefan problems．The effect of molding conditions on the cooling temperature of HDPE was also discussed,which can reflect the change of its crystalline hehavior.
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发布时间：2021-03-19 - 摘要：Water diffusion coefficients and dynamics at adhesive/C-C composites joints were calculated with EDX analysis．For this method does not break the adhesive joints,it’s much simpler than the calculation of water diffusion coefficients and dynamics with elemental analysis．Until now this method was not introduced in referenees Water diffusion coefficients and dynamics in adhesive/C-C composites joints treated by different surface treatment methods were also studied．It was indicated that the water diffusion speed in adhesive/C-C composites joints treated by sand paper was the fastest as compared to those treated by chemical oxidation and by silane couple agent treatment．
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发布时间：2021-03-19 - 摘要：A liquid urethane prepolymer encapped with vinyl ether groups (PUE),was synthesized and characterized．PUE and triethylene glycol divinyl ether (DVE-3) can undergo rapid cationic thermal polymerization in the presence of diphenyliodonium hexafluorophosphate (H810) at different temperatures．The polymerization conversion of vinyl ether is pretty high．Thermal polymerization temperature for these systems is much lower than the decomposition temperature of neat P1810．The initiation mechanism is presumably based on electron transfer from eleetron-rich vinyl ether to electron-deficient diphenyliodonium salt The influence of vinyl ether on the thermal polymerization of epoxy resin/diphenyJiodonium salt was also investigated.
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发布时间：2021-03-19 - 摘要：Poly (methyl methacrylate)/vermiculite PMMA/VMT nanoeomposites were synthesized by emulsion polymerizations in aqueous dispersions containing vermiculite which were modified by methacryloyloxyethyl trimethyl ammonium chloride (DMC) The structure of the nanocomposite was investigated by XRD,FT-IR,DSC and TGA．The results shows that exfoliate structures of vermiculite exist in the PMMA/VMT nanocomposites．ThelTilal decomposition temperature and glass transition temperature of PMMA/VMT nanocomposites have been improved at lower VMT contents(≤1.0 wt％)．The reaction rate of polymerization decreased with adding vermiculite modified by DMC．The viscosity average molecular weiight of PMMA/VMT nanocomposites has been in creased．
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发布时间：2021-03-19 - 摘要：The preparation of a kind of porous hdlow oxidation fiber based on ultrahigh molecular weight polyacrylonitrile (UHMW-PAN) as precursor is presented．The effects of preparation technology conditions,oxidation temperature and oxidation time,on degree of ring formation of porous：hollow oxidation fiber ale studied in details．It shows that degree of ring formation is increasing with increasing of oxidation temperature and time．Comparing with normal molecular weisht polyacrylonitrile (CMW-PAN) based solid fibers,the oxidation temperature of porous hollow fiber based on UHMW-PAN should be low (<240℃),and oxidation time should be short(<2 h)．
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发布时间：2021-03-19 - 摘要：The sodium alginate(SA)/poly(N-isopropylacrylamide) (PNIPAM) semi-interpenetrating (semi-IPN) hydrogel was prepared by incorporating SA into cross-linked PNIPAM to form a semi-IPN polymeric network．The properties of the semi-IPN hydrogel were characterized by DSC and SEM．The influences of the amount of SA in the semi-IPN hydrogel,pH and temperature on the swelling rates of these hydmgels have been thoroughly investigated．It is showed that at a temperature below the lower criffical solution temperature (LCST) and pH=7.4 the swelling rate increases with increasing SA content in the semi-IPN hydrogel and relies on the relaxation rate of macromolecular chains in the hydrogel network．In addition,the effect of pH value on the swelling rate depends on temperature,while the effect of temperature on the swelling rate is also associated with pH value.
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发布时间：2021-03-19 - 摘要：Porous polymeric materials could be successfully prepared by gamma radiation polymerization of BA- containing micmemulsions．The main aims of this paper are txying to control the pore structures of the polymer obtained by mlcroemulsion polymerization and to alleviate the occurrence of phase separation during the polymerization of miememulsions．The emulsifier systems,including a nonionic mixture of OP-4 and OP-10,an anionic-nonionic mixture of SAO and OP-10,a cationic-nonionie mixture of CTAB and OP-4,could be used successfully to prepare stable,transparent mieroemulsions,which have different bicontinuous phase range The resulting polymers were studied by scanning electron microscopy (SEM)．It was found that their morphology characteristics strongly depended on the composition (water content,crosslinker content,functional comonomer) of the precursor microemulsions．
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发布时间：2021-03-19 - 摘要：Three kinds of core-shell polyacrylate latices (abbreviated to P(BA-EHA),ACR I and ACRⅡ) were synthesized by muhi-stage emulsion polymerization．Butyl acrylate,2-ethylhexylacrylate and 1,4-butanediol diacrylate were used as components of the ACR core,while butyl acrylate/2-ethylhexylacrylate or methyl methacrylate/styrene or methyl metbacrylate/ethyl acrylate were employed as components of the ACR shell,respectively．Using ACR latices as seeds,three kinds of ACR-g-PVC resin were prepared by seeded emulsion co-polymerization with vinyl chloride． The structure and sizes of ACR and composite latex particles were investigated through transmission electron microscopy and dynamic laser scattering method．The morphology and impact toughness of the obtained materials were characterized．It was found that the notched impact strength of the three kinds of ACR-g-PVC materials at room temperature was enhanced with an increasing ACR content．The abrupt increment of the notched impact strength for the ACR-g-PVC materials happened at the same rubbery content of about 4％．This was explained by the change of interparticle distance. The toughening efficiency of P(BA-EHA) was higher than that of ACR I or ACRⅡ．The toughening efficiency of ACR in the materials was discussed according to two ideal-structure models of the ACR-g-PVC composite particles．
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发布时间：2021-03-19 - 摘要：Four types of chitosan beads,carboxylic chitosan (SUC-CS),benzoyl chitosan(BEN-CS), polyethyleneiminated ehitosan (PEI-CS) and quatemaminated chitosan (QA-CS) were prepared using the wet phase-inversion method and chemical modification with the chemicals of succinic anhydride,benzoic anhydride,polyethyleneimine and 3-chloro-2-hydroxypropyltrimethyl ammonium chloride． Carboxyl, aromatic acyI,polyethyleneimine and quaternary ammonium groups were induced to chitosan chains,and their structure was characterized by FTIR spectra．The adsorption ability of the chemically modified ehitosan resins to nine kinds of diuretics was investigated．The results show that,compared to the unmodified chitosan,the benzoyl chltosan has higher affinity and capacity to almost all the diuretics due to the hydrophobie interaction between chitosan and dmg molecule,while the earboxyl chitosan has higher binding affinity only to the basic diuretics．The polyethyleneiminated chitosan has 48％～209％higher capacity to the acidic diuretics due to the increased concentration of amino groups on its chain．The adsorption ability of quatemaminated chitosan for the diuretics with carboxyl group is greatly improved,especially for the bumetanide,which is above 2 times higher than the unmodified one because of the strong interaction of ion exchange．
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发布时间：2021-03-19 - 摘要：γ-Ray irradiation was successfully used in the surfactant-free emulsion copolymerization of N,N’-methylenebisacrylamide(Bis) and 4-vinylpyridine(4-VP),leading to a series of microgels with average hydrodynamic radius(Rh) ranging from 56 nm to 152 nm. However,when acrylic acid(AA),methacrylic acid(MAA) or acrylamide(AM) were used instead of 4-VP,unstable white emulsions or white bulk gels were obtained．The poly (N,N’-methylenebisacrylamide-co-4-vinylpyridine)(poly(Bis-co-4-VP))micmgels were characterized by infrared spectroscopy,differential scanning calorimetry and transmission electron microscopy．The effects of the ratio of monomers,absorbed dose and dose rate on the synthesis of paly(Bis-cos-4-VP) mierogels were studiedthrough Rh,absorbance and gel ratio．The results showed that the size of microgels could be controlled either by the absorbed dose or by the ratio of monomers．The mechanism concerning the formation of microgels was also discussed．
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发布时间：2021-03-19 - 摘要：The effeet of the network structure on the swelling behavior of ethyl-cyanoethyl cellulose(E-CE)C/cross-linked polyacrylic acid(PAA) cholesteric liquid crystalline composite films was studied．It was found that the equilibrium swelling ratio (Rs(e)) of the composite films with different thickness is the same．The thicker film needs the longer time to reach the equilibrium swelling state．The (E-CE) C concentration of the composite films has little effect on Rs(e),but Rs(e) decreases with increasing the concentration of the cross-linking reagent．It was indicated that with increasing the concentration of cross-linked reagent,the structure of the film becomes mole compact and it is more difficult to infiltrate water into the film．The time to reach the equilibrium state for the composite films with different concentration of cross-linking reagent is almost the same．
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发布时间：2021-03-19 - 摘要：Long-chain branched polyethylene was obtained using a homogeneous bianary catalyst system composed of late and early transition metal complexes,namely a mixture of bis(α-naphthalidine)-2,3-butanediimine) NiBr2 and Cp* TiCl3,as catalyst precursors in the presence of MAO．The binary catalyst system shows a good synergic effect,the polymerization activity is as high as 6×105g PE/mol(Ni+Ti)·h at i>XNi=0.8 and higher than that of either single Ni or Ti catalyst．The structure of PE was confirmed by 13C-NMR not only containing methyl,ethyl,butyl,amyl side groups,but also significant amount of long chain branches(n≥6)．The explanation for this is that ethylene oligomerized in the Ni catalyst active site and the oligomers containing vinyl end group served as comonomers to in situ copolymerize with the growing polyethylene chain in the active site of titanium catalyst．GPC curve of the resulting polyethylene obtained with this binary catalyst system showed a bimodal molecular weight distribution.
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发布时间：2021-03-19 - 摘要：A catalyst system Cp*TiCl2N[Si(CH3)3]2/methylalmninoxane(MAO)has been used for atactic polymerization of propylene．The polymerization performed in a l L autoclave at 0℃～50℃ with heptane as solvent．The atactic polypropylene has high molecular weight (Mw=20×104～60×104) with Tg=8.8℃．The polymers have high stereo irregularity and contain ether-soluble fractions over 94％．The effects of polymerization temperalure,concentration of MAO and pressure of monomer on the catalytic activity and molecular weight of the polymer were studied in detail. The structure and properties of the polymers were characterized by DSC, 1H-NMR and DMA.
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发布时间：2021-03-19 - 摘要：The fluorescence and absorption spectra were applied for studying the interaction of 1-bromo ethyl benzene——a component in initiation systems of ATRP and some amino ligands which were used for the copper(I) complex formation．It was found that when the 2,2'-bipyridyl was used as a ligand for metal complex formation,an abnormal new peak was observed obviously whether in fluorescence or absorption spectrum．It indicated that a new species was formed owing to the reaction between them．However,when the aliphatic amines such as tetra methylethylene-diamine and pentamethyldiethylene-tfiamine were used,especially the molar ratio of metal/ligand of complex is 1/4,an evident exciplex emission can be observed in the spectrum．All of these phenomena,especially the chemical reaction occurred in the bipyridyl system will result in unfavorable effects for the ATRP process．And the exciplex formation which was occurred in excited state in aliphatic amine systems will not affect the ATRP process as serious as salt formation in the system of bipyridyl．
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发布时间：2021-03-19 - 摘要：New conjugated rigid-rod polymers,poly(p-phenylene-benzobisoxazole) (PBO),poly(benzabiso-xazole-2,6-diylvinylene) (PBOV),and poly(benzobisoxazole-2,6-diyldivinylene) (PBODV) were synthesized,and their molecular structures．thermal stabilities and morphology of polymers were determined by FTIR,1H-NMR,TGA and WAXD respectively．The photophysical properties of polymer／MSA solutions were investigated by UV and photoluminescence spectroseopies The UV spectra and photoluminescence spectra of these new polymers in methanesulfonic acid suggest that the absorption spectra and optical bandgap of PBODV and PBOV have a red shift compared with those of the conjugated PBO. That is caused by the different conjugation structures in molecular chains of PBO,PBOV and PBODV.
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发布时间：2021-03-19 - 摘要：Ambedite XAD-4 polymeric resin was chemically modified with an amino group,which enables the resin (NDA-100) to be used directly without a wetting process．The adsorption thermodynamic and kinetic behaviors of phenol and p-hyamxybenzoic acid on NDA-100 were studied．A batch sorption experiments showed that NDA一100 resin had high sorption capacities for both phenolic acids Equilibrium adsorption data fitted to both Langmuir and Freundlich isotherms in the studied concentration range．Adsorption was exothermic and basically of physical character．Kinetic analysis showed that the adsorption reaction could be approximated by a Lagergren pseudo-second-order-rate equation for which intraparticle diffusion was the essential rate-controlling step．
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发布时间：2021-03-19 - 摘要：Q-CdS nanoparticles(d<10 nm) were prepared by synthetic methods of coordination chemistry Then a seNes of Q-CdS/polymer nanaocomposite films were successfully prepared by mixing Q-CdS with polymers．Their size quantization effect and dispersion were observed in UV-Vis spectra and TEM image．Fluorescent properties of nanocomposite films of different kind polymers or different Q-CdS contents,were studied by fluorescent spectra．Compared to CdS nanoparticles or pure polymers,nanoeomposite films which were made of polymer and Q-CdS have special fluorescence spectra due to interaction between them．The fluorescence intensity of nanocomposite films increased with the Q-CdS nanoparticle content,showing a maximum at the ratio Q-CdS/Polymer=0.067/1 by wt.
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发布时间：2021-03-19 - 摘要：High-impact polystyrene (HIPS)/organomontmorillonite (Org-MMT) nanocomposites and HIPS/inorganic montmorillonite (MMT) conventional composites were prepared by melt processing using a twin-screw extruder．Their thermal and theological properties were studied by using TGA and capillary theometer,respectively．The differences in properties between the two types of composites were examined．The results show that the nanocomposite has better thermal stability and flowing properties than pristine HIPS or the conventional composite,and the former has a more outstanding shear-thinning behavior．In addition,when the montmorillonite is dispersed in nanoscale,the surface quality of the composites is improved evidently.
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发布时间：2021-03-19 - 摘要：A novel blend composition was prepared based on chlorinated butyl rubber (CIIR) and poly (meth) acrylate (PMAc)．The results obtained from DMA,DSC measurements show that it is possible to shift the effective damping functional region of CIIR toward higher temperature region whether the blend composition was prepared with a co-crosslinking system or a non-co-crosslinking one．FTIR analysis and extractive experiments demonstrate the existence of a co-crosslinking structure between CIIR and PMAc in the blend and TEM discovers that it is the co-crosslinking between CIIR and PMAc that varies the mieroeopie morphology of CIIR/PMAC blends．All the facts show that mixing PMAc of different composition and structure with CIIR results in the suppression of the Tg and Tn transition of CIIR,and consequently,CIIR/PMAc blends exhibit different damping behavior according to whether they are in a co-erosslinking system or in a non-co-crosslinking system．
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发布时间：2021-03-19 - 摘要：Iron(Ⅲ)acetylacetonate[Fe(aeac)3] was used as catalyst for the ring-opening polymerization of D,L-lactide and copolymerization of D,L-lactide with polyethylene glycol (PEG)．The effects of catalyst content,reaction temperature,polymerization time and D,L-lactide/PEG molar ratio were investigated．It was showed that the polymerization conversion of lactide more than 90％ could be obtained and polylactide (PDLLA) with viscosity-average molecular weight up to 66000 was prepared．Experimental results indicated that the ring-opening polymerization of lactide proceeded via a coordination-insertion mechanism．Analysis by 1H-NMR showed that PEG acted as an initiator participated in initiation of the ring-opening polymerization of lactide,while Fe (acac)3 promoted the esterification of PEG with lactide．The lactide chains grew from both ends of the PEG molecules and ended with hydroxy-terminated lactyl units．
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发布时间：2021-03-19 - 摘要：Four novel poly(aryl ether-ketone-ether-ketone-ketone)s(DM-PEKEKK,DM-PEKEKMK) and poly(aryl ether-ketone．ketone-ether-ketone-ketone)s(DM-PEKKEKK,DM-PEKKEMK),containing bis(o-methyl) moiety were prepared by electrophilic polycondensation of 2,2’,6,6'-tetramethyl-4,4'-diphenoxydiphenylketone (o-M2DPOBP) or 2,2’,6,6'-tetramethyl-4,4'-diphenoxytriphenyldiketone (o-M2DPOTPDK) and terephthaloyl chloride(TPC) or isophthaloyl chloride(IPC) in 1,2-dichloroethane and in the presence of AlCl3 and DMF．The polymers were characterized by FT-IR,WAXD,DSC,1H-NMR,TGA and there solubility properties were tested．The results show that the polymers have high slass transition temperature,good thermostabilities and excellent solubilities.
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发布时间：2021-03-19 - 摘要：The micellization of thermo-responsive dextran-g-PNIPAM copdymem in aqueous solutions was studied by means of surface tension technique．The surface tension of the aqueous solutions of the graft copolymers was determined overthe concentration range of 0.0001 wt％ to 0.5 wt％ at two temperatures(15 and 37℃)．It was found that the absorption of the grit polyrners at the air/water interface behaved in a dynamic way．The critical micellization concentration (CMC) of the eopolymers was determined from euives of the surface tension versus lg concentration The micellization behavior depended closely on the grafting of the copolymers and the aqueous solution temperature．Micelles could be formed in the lower concentrations when increasing PNIPAM contents of the copolymers or raising the aqueous solution temperature More importantly,the eopolymers showed CMCs in all cases no mater whether the temperature was hisher than the phase transition temperature(LCST) of the eopolymere or not．An explanation was given for understanding the phenomenon.
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发布时间：2021-03-19 - 摘要：Epexy/rectorite nanocomposites were prepared successfully by dispersing organically modified rectorite in a kind of epoxy resin．XRD and TEM results indicated that the intercalated and exfoliated structures were observed,and it was found that in composites with lower rectorite contents the rectorite was easier to form exfoliation structurte．FT-IR spectra showed that the reaction between the rectorite and epoxy matrix occurred．At low rectofite contents,the mechanical and thermal properties of the nanocomposites have significant improvements in temas of the impact strength,the breaking elongation and the glass transition temperature compared to the neat epoxy,which indicates that the large surface area of rectorite platelets and their strong interaction with epoxy resin can restrict the motion of polymeric segments．then improve the mechanical and thermal properties．When the rectorite content>0.8 wt％,the properties of nanocomposites become poorer and poorer．It can be explanied as that the exfoliated structure is more desirable in enhancing the properties of nanocomposites,but too nmny platelets of rectorite may destroy the continuity of the matrix．
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发布时间：2021-03-19 - 摘要：A novel late transitional metal catalyst-(2-Me-3-ClPh)2PBIMe2FeCl2——has been synthesized having a high oligomerization activity up to 1.0×107g oligomed(mol Fe·h)．Using this oligomerization catalyst and metallocene catalyst—rac—C2H4(Ind)2ZrCl2in situ copolymerization of ethylene having a high activity[ >106g PE/(mol cat·h)]．13C-NMR shows that the LLDPE is obtained．In addition,the presence of unreacted α-olefin was not detected since there is no evident resonance signal at 29．29 and 29．42．which proves that this dual functional catalyst system has a good match during in situ copolymerization．With increasing the Fe/Zr ratio,the densities of polymers and the melting points of polymers obtained from DSC ale in a descending trend．Meanwhile,the similar phenomenon is also found when the reaction temperature decreases．
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发布时间：2021-03-19 - 摘要：The surface compositions of a series of block and graft copolymers of polystyrene-polydimethylsiloxane was investigated by attenuated total reflectance(ATR-FTIR)and X-ray photoelectron spectroscopy(XPS).It was shown that enrichment of PDMS soft segments occurred on the surface of the block copolymers as well as on that of graft copolymers．The degree of enrichment of PS-b-PDMS was larger than that of PS-g-PDMS,which was explained as a result of the easiness of movement of the PDMS segments of PS-b-PDMS．Meanwhile．the solvents of different solubility parameter and the contact medium of different polarity had different influence on the enrichment of PDMS on the surface．The surface energy measurement further confirmed that the diblock copolymers tended to have higher surface enrichment of the PDMS segments than that of the graft copolymers．
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发布时间：2021-03-19 - 摘要：Addition of elastomer to PP can greatly improve its impact resistance,but at the cost of decrease in properties like stiffness and heat resistance．Introduction of inorganic particles into PP can lead to faidy high stiffness,but at the cost of lower fracture toughness．Therefore,to improve the overall performance of PP,a ternary blending method of PP with both rigid inorganic particles and soft elastomefic inclusions has attracted much attention because of its potentiality in achieving both high stiffness and high toushness．A new ternary nanocomposite of PP/styrene-butadiene rubber/nano-CaCO3 was prepared by melt-blending,and its properties and crystallization behavior were investigated．TEM photographs show that the nanocomposite has a“sea-island”microstructure with a“salami” like structure in the dispersion phase,where the nano-CaCO3 particles are embedded in styrene-butadiene rubber particles,This unique phase structure gives the PP nanocomposite excellent pmperties in impacl resislance,stiffness, heat resistance and crystallization rate. Also studied were the effect of the introduction of sodium benzoate and the content of nano-CaCO3 on the ternary PP nanocomposite’s phase structure．crystal form and crystallization kinetics and the effect of the particle size of dispersion phase and the content of βcrystal on the nanocomposite’s properties．It was found that increase of the content of nano-CaCO3 particles and introduction of sodium benzoate into PP ternary system lead to a decrease of the dispersion phase particle size within PP matrix and a great increase of crystallization rate,and consequently result in the remarkable improvement of impact resistance,stiffness and heat resistance of the PP composite．
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发布时间：2021-03-19 - 摘要：An alkali-soluble random eopolymer P(MMA/EA/MAA) was synthesized and used as a polymeric surfactant in emulsion polymerization of butyl methacrylate. The latex was studied by transmission electron micrograph,and a core/shell morphology was found for the latex particles．The effects of polymerization temperature,and amount of initiator and surfactant on polymerization rate were investigated．The results show that polymerization rate increased with the concentration of the initiator and the surfaetant．The relationship between Rp and concentration of initiator is Rp ∝[I]0.52．The apparent activation energy of the emulsion polymerization is 85.19 kJ·mol-1.
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发布时间：2021-03-19
Research Article
- 摘要：A monomer of 4-[(acryloxy) methyl]-4-ethyl-2-oxazolidinone(AEO) was synthesized and characterizedby 1H-NMR spectra．Graft polymerization of AEO on ceUulose fibers could be carried out using ammonium cerium (Ⅳ) nitrate as initiator．The grafted fibers were characterized by FT-IR and the morphology of the surfaces wasinvestigated by using Scanning Electronic Microscopy．The optimum conditions for graft polymerization were investigated in detail．It Was found that increasing the concentration of AEO caused an increase of grafting yield and grafting efficiency．An optimum temperature existed in cases of high monomer concentration resulting in the highest grafting efficiency．The optimum concentration of initiator was about 3 mmol／L．The proper grafting polymerizationtime was about 60 min.
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发布时间：2021-03-19 - 摘要：A quaternary ammonium salt (QAS),Methacryloxylethfl benzyl dimethyl ammonium chloride,was introduced onto the surface of PE films by UV photografting technique．The photografted films were characterized by FTIR．XPS and SEM．Morphology of the grafted layers were studied and was found to change with th UV Light irradimion time．The PE film surfaces were uniformly covered with the QAS moieties and the thickness was about several μm．A clear boundary between the grafted layer and the substrate surface was also observed．
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发布时间：2021-03-19
Research Bulletin
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