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1.
以苯乙烯(St)和马来酸酐(MAH)为主要原料、单链脂肪醇(脂肪醇中碳原子数n=4、5、6、8)为改性剂,通过在主链中引入软单体丙烯酸丁酯(BA),成功制备出改性P(St/MAH/BA)和P(St/MAH)系列施胶剂。结果表明:在相同条件下,经改性P(St/MAH)或P(St/MAH/BA)施胶剂施胶后,不同施胶纸具有不同的施胶效果;对文化书写纸而言,前者的油墨吸收率高于后者、平滑度小于后者,但两者的拉伸强度和施胶度差别不大;对瓦楞纸而言,前者的施胶度和环压强度均高于后者。随着单链脂肪醇中碳原子数的不断增加,文化书写纸的油墨吸收率增大、平滑度和拉伸强度下降,而瓦楞纸的环压强度增大、拉伸强度略有下降,但两种施胶纸的施胶度均呈先升后降态势。  相似文献   

2.
Copolymerization of 4-vinylpyridine (4VP) with styrene (St) was performed in ethanol using 2,2′-azobisisobutyronitrile (AIBN) as an initiator, and then a random copolymer P(4VP–St) was obtained. A soluble pyridinium-type polymer containing N-benzyl-4-vinylpyridinium bromide [Q-P(4VP–St)], was prepared by quaternization of P(4VP–St) with benzyl bromide (BzBr). The structures of P(4VP–St) and its quaternized product Q-P(4VP–St) were identified by FTIR. The 4VP content in P(4VP–St) and the pyridinium group content (Cq) in Q-P(4VP–St) were determined by nonaqueous titration and argentometry, respectively. The molecular weight of p(4VP–St) was characterized by intrinsic viscosity. In addition, the charge density σ of the soluble pyridinium-type polymers was measured by colloid titration, and the mathematical relation between σ and Cq was established as follows: σ = −0.090 + 0.942 Cq. A preliminary investigation was made into the viscosity behavior and electroconductivity of the Q-P(4VP–St)/polar solvent system. © 1996 John Wiley & Sons, Inc.  相似文献   

3.
This study concentrates on the transverse low-speed impact behavior of adhesively bonded similar and dissimilar clamped plates using the three-dimensional explicit finite element method. The contact force and plastic dissipation histories of the adhesively bonded dissimilar plates, such as aluminum–aluminum (Al–Al), aluminum–steel (Al–St), steel–aluminum (St–Al) and steel–steel (St–St) layered structures, were studied for different values of the impactor mass, radius and velocity (impact energies). The residual plastic strains in both adhesive layer and plates increased with increasing impact energies. The impactor radius had only a minor effect on the contact force histories for all configurations. The peak transverse deflection in the impact region was maximal in Al–Al, decreased in Al–St, St–Al plates and became minimal in St–St bonded plates. Impact effect was evident in the back plates of all four configurations. Al–Al plates dissipated impact energy as much as the adhesive layer, whereas the adhesive layer rather than plates absorbed the impact energy in Al–St, St–Al and St–St bonded plates and this state became evident in the St–St bonded plates. The number and locations of the steel plates considerably affected impact force history, impact time as well as the plastic dissipation level; thus, the contact force increased, the contact time shortened and the dissipated energy decreased. As the impact energy was increased the impact period got longer. Damage areas in the adhesive layer were minimal in Al–Al bonded plates but maximal in St–St bonded plates.  相似文献   

4.
在脲醛树脂(UF)/淀粉(St)复合体系中引入聚醋酸乙烯酯(PVAc)、聚丙烯酰胺(PAM),氨基硅烷偶联剂(A212),通过力学性能测试和扫描电镜分析研究了复合体系的常温固化过程、材料微观结构及其性能变化的关系。结果表明,当m(UF)/m(St)/m(PVAc)/m(固化剂CA)/m(PAM)/m(A212)=200/50/2/3/5/0.06时,体系冲击强度为190kJ/m2,弯曲强度为24MPa。PVAc的引入延长了体系的固化时间,PAM较好地改善了体系的分散状态。A212明显改善了体系分散的均匀性和相界面结合状态,材料微观结构更为致密,力学性能提高,尤其是韧性明显改善。  相似文献   

5.
Binary and ternary experimental cloud‐point curves (CPCs) for systems formulated with a low molar mass synthesized divinylester (DVE) resin, styrene (St), and poly(methyl methacrylate) (PMMA) were determined. The CPCs results were analyzed with the Flory–Huggins (F‐H) thermodynamic model taking into account the polydispersity of the DVE and PMMA components, to calculate the different binary interaction parameters and their temperature dependences. The St‐DVE system is miscible in all the composition range and down to the crystallization temperature of the St; therefore, the interaction parameter expression reported for a higher molar mass DVE was adapted. The interaction parameters obtained were used to calculate the phase diagrams of the St‐PMMA and the DVE‐PMMA binary systems and that of the St‐DVE‐PMMA ternary system at three different temperatures. Quasiternary phase diagrams show liquid–liquid partial miscibility of the St‐PMMA and DVE‐PMMA pairs. At room temperature, the St‐DVE‐PMMA system is miscible at all compositions. Final morphologies of PMMA‐modified cured St‐DVE materials were generated by polymerization‐induced phase separation (PIPS) mechanism from initial homogeneous mixtures. SEM and TEM micrographs were obtained to analyze the generated final morphologies, which showed a direct correlation with the initial miscibility of the system. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 4539–4549, 2006  相似文献   

6.
SBS/P(St-MMA)热塑性互穿聚合物网络结构与力学性能   总被引:1,自引:0,他引:1  
采用原子转移自由基聚合(ATRP)法合成了苯乙烯一甲基丙烯酸甲酯共聚物[P(St-MMA)]。采用分步法制备了SBS/P(St-MMA)热塑性互穿聚合物网络(TIPN)。研究了P(St-MMA)质量分数、MMA/St(摩尔比,下同)和不同聚合方式对TIPN结构和力学性能的影响。结果表明:生成了具有较窄相对分子质量分布的P(St-MMA);P(St-MMA)质量分数在30%,左右时,采用ATRP法制备的SBS/P(St-MMA)TIPN拉伸强度和扯断伸长率达到最大;随MMA/St增加,TIPN拉伸强度增大,扯断伸长率不变。常规自由基聚合法制备的TIPN与ATRP法相比,前者相对分子质量高,相对分子质量分布宽,拉伸强度高,扯断伸长率随P(St-MMA)质量分数增加而下降。  相似文献   

7.
在苯乙烯(St)存在下,将含不饱和键和异氰酸酯双官能团的单体m-异丙烯基-α, α-二甲基苄基-异氰酸酯(m-TMI)熔融接枝到聚丙烯(PP)上,分别采用无水滴定法、红外光谱、热重分析和差示扫描量热法对接枝产物进行测试。结果表明,m-TMI、St均与PP发生接枝反应,并且St的存在能够有效抑制PP在接枝过程中的降解,提高m-TMI与PP的接枝产物的热稳定性。在保持St用量不变的条件下,m-TMI的接枝率和接枝效率随其用量的增加先增大后减小;在保持m-TMI用量不变的条件下,m-TMI的接枝率在St与m-TMI的摩尔比为1.6时达到最大值。  相似文献   

8.
In this study, maleic anhydride (MA)–styrene (St)–allyl propionate (AP) was produced with MA, St, and AP. It was then reacted with n‐propyl alcohol (Pr), n‐butyl alcohol (Bu), n‐pentyl alcohol (Pn), and benzyl alcohol (Bz) under certain conditions to produce ester derivatives of the terpolymer. These ester derivatives were designated alkyl maleate terpolymers (PrMA–St–AP, BuMA–St–AP, PnMA–St–AP, and BzMA–St–AP). The polymers were investigated by solubility and viscosity experiments, with the number of ester groups in the polymers determined by chemical analysis. They were also characterized by Fourier transform infrared spectroscopy, with thermomechanical properties measured via stress–strain curves. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 296–299, 2003  相似文献   

9.
The copolymers of 4‐vinylpyridine (4VP), styrene (St) and divinylbenzene (DVB) with varied compositions, P(4VP‐St‐DVB), were synthesized by suspension polymerization using 2,2′‐azobisisobutyronitrile (AIBN) as an initiator. The insoluble (crosslinked) pyridinium‐type polymers in benzyl–pyridinium bromide form, which possess various macromolecular chain compositions, were prepared by the reaction of each P(4VP‐St‐DVB) with benzyl bromide (BzBr), respectively. By using different halohydrocarbon RX in the quaternization of P(4VP‐St‐DVB), the insoluble pyridinium‐type polymers with various pyridinium group structures were obtained. The structures of P(4VP‐St‐DVB) and its quaternized product Q‐P(4VP‐St‐DVB) were identified by FTIR. The 4VP content in each copolymer P(4VP‐St‐DVB) was measured by nonaqueous titration; and the pyridinium group content (Cq) in each Q‐P(4VP‐St‐DVB) sample was determined by means of the back titration manner in argentometry and/or the elemental analysis method, respectively. In addition, the particle structure and the surface morphology of the thus‐prepared polymer were observed using SEM. According to a series of experimental results, the preparation and characterization of insoluble pyridinium‐type polymers are analyzed and discussed. This work can prepare the ground for a study on the antibacterial activity of insoluble pyridinium‐type polymers. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 668–675, 2000  相似文献   

10.
Fairly uniform copolymer particles of methyl acrylate (MA), butyl acrylate (BA), or butyl methacrylate (BMA) were synthesized via Shirasu porous glass (SPG) membrane and followed by suspension polymerization. After a single‐step SPG emulsification, the emulsion composed mainly of the monomers. Hydrophobic additives of dioctyl phthalate (DOP), polystyrene molecules, and an oil‐soluble initiator, suspended in an aqueous phase containing poly(vinyl alcohol) (PVA) stabilizer and sodium nitrite inhibitor (NaNO2), were subsequently subjected to suspension polymerization. Two‐phase copolymers with a soft phase and a hard phase were obtained. The composite particles of poly(St‐co‐MA)/PSt were prepared by varying the St/PSt ratios or the DOP amount. The addition of PSt induced a high viscosity at the dispersion phase. The molecular weight slightly increased with increasing St/PSt concentration. The multiple‐phase separation of the St‐rich phase and PMA domains, observed by transmission electron microscopy, was caused by composition drift because the MA reactivity ratio is greater than that of St. The addition of DOP revealed the greater compatibility between the hard‐St and soft‐MA moieties than that without DOP. The phase morphologies of poly(St‐co‐MA), poly(St‐co‐BMA), and their composites with PSt were revealed under the influence of DOP. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1195–1206, 2006  相似文献   

11.
以苯乙烯(St)、甲基丙烯酸甲酯(MMA)和丙烯酸丁酯(BA)为共聚单体,丙烯酸(AA)为功能单体,反应型乳化剂(DNS-86)、十二烷基硫酸钠(SDS)和壬基酚醚磺基琥珀酸酯钠盐(OS)为复合乳化剂,采用种子乳液聚合法制备了粒径小、耐水性好且固含量为50%的苯丙微乳液。研究结果表明:当w(引发剂)=0.7%、m(MMA+St)∶m(BA)∶m(AA)=5.0∶4.7∶0.3、w(St)=15%~25%、m(DNS-86)∶m(SDS+OS)=3∶2且w(复合乳化剂)=5%时,高固含量苯丙微乳液的综合性能良好。  相似文献   

12.
Two concentrated emulsions in water were prepared: one from weakly polymerized butyl methacrylate (BMA) and the other one from a weakly polymerized mixture of acrylonitrile (AN) and styrene (St). Each of the concentrated emulsions also contained a small amount of a vinyl-terminated macromonomer (VTM). After the concentrated emulsions were partially polymerized, they were mixed and subjected to complete polymerization. This generated a blend of poly(butyl methacrylate) (PBMA), binary copolymer AN-co-ST (AN—St), and networks containing chains of VTM and those formed from different monomers. The networks constitute compatibilizers between the PBMA and AN—St. Such a preparation method, in which the components and compatibilizer are generated simultaneously, was called self-compatibilization. The blend possesses excellent tensile properties and toughness compared with the ternary copolymer AN—St—BMA and with the solution blends of PBMA/AN—St. The generation of the compatibilizers and the compatibilization mechanism were investigated via kinetic studies. The effects of the VTM, polymerization conditions, and the weight ratio of AN/St were also examined. © 1996 John Wiley & Sons, Inc.  相似文献   

13.
以丙烯酸丁酯(BA)和苯乙烯(St)为改性剂、双丙酮丙烯酰胺(DAAM)为交联剂,采用自由基引发聚合工艺,制备出高性能的BA/St改性水性聚氨酯(WPU)包装用胶粘剂。采用红外光谱(FT-IR)仪和粒度分析仪对乳液的结构和性能进行了分析,讨论了R值(即-NCO/-OH的物质的量比)、改性剂、St和交联剂用量对胶粘剂粘接强度的影响。试验结果表明:当R=1.1、w(改性剂BA/St)=28%(相对于WPU而言)、w(St)=30%(相对于BA/St而言)和w(DAAM)=2%时,乳液的粘接性能最佳;由该乳液配制的胶粘剂可以满足多种复合软包装膜的使用要求。  相似文献   

14.
Graft copolymerization of acrylic acid (AA) onto starch was carried out with ceric ammonium nitrate as initiator under nitrogen atmosphere. The grafting percentages (GP%) of starch‐graft‐AA (St‐gr‐AA) copolymers were determined. When the AA molar concentrations were 0.3 and 0.5 mol/L, GP% of St‐gr‐AA copolymers were 10.5% (St‐gr‐AA‐1) and 14% (St‐gr‐AA‐2), respectively. St‐gr‐AA copolymers have been used for the adsorption of basic dye (Safranine T) from aqueous solutions. Effects of various parameters such as treatment time, initial pH of the solution (pH = 2–6), initial dye concentration (50– 500 mg/L), and GP% of starch graft copolymers were investigated.Basic dye removal capacities of the copolymers increase along with the augment of initial concentration of the adsorbate, GP% of the copolymers, and pH. The adsorption capacities for St‐gr‐AA‐1 and St‐gr‐AA‐2 reach 116.5 and 204 mg/g, respectively. Equilibrium adsorption data were obtained and fitted very well to Freundlich model. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007  相似文献   

15.
Summary The A-B diblock copolymers with comb shape structure were prepared from styrene (St) and either methacrylate of poly(ethyleneglycol) monomethyl ether (MPEGM) or methacrylate of poly(ethyleneglycol) (HPEGM). The surface chemical analysis of the polymer at air-solid interface by means of X-ray photoelectron spectroscopy (XPS) revealed the enrichment of MPEGM for MPEGM/St and St for HPEGM/St diblock copolymers, which indicated that the end group of the side chain determined surface composition. Dynamic contact angle measurements revealed that the migration of hydrophilic poly(ethyleneglycol) at solid-water interface occurred upon immersing the film specimen in water.  相似文献   

16.
Cationic copolymer emulsions of St, BA, AA, and GMA were successfully synthesized via semi‐continuous emulsion polymerization. The properties of synthesized cationic emulsions were characterized by monomer conversion and solid content, differential scanning calorimeter, particle size and distribution, zeta potential, and centrifugal stability. The film performance of the cationic emulsions formed on cotton fiber surface was observed by scanning electricity microscopy. The influence of cationic emulsions on the color data, K/S values and rubbing fastness of dyed cotton fabrics was also investigated. The results show that P (St‐BA‐AA‐GMA) emulsion had larger particle size and higher zeta potential than P (St‐BA‐AA) emulsion. When the films were formed at room temperature, P (St‐BA‐AA‐GMA) emulsion film had better performance than P (St‐BA‐AA) emulsion film. The addition of GMA monomers improved the film performance. P (St‐BA‐AA‐GMA) emulsion films formed at 120 °C after acetic acid solution treatment had the best water resistance. Dyed cotton fabrics pretreated with P (St‐BA‐AA‐GMA) emulsion had better pigment dyeing performance than those pretreated with P (St‐BA‐AA) emulsion. It demonstrates that the addition of GMA monomers further improved the effect of pigment dyeing for cotton fabrics with cationic emulsions as binders. With the increase of P (St‐BA‐AA‐GMA) concentration, the color performance of dye fabrics improved while the rubbing fastness decreased a little. But, the handle and fastness still meets the use standards for consumers. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44987.  相似文献   

17.
Active macromolecular free radicals were generated on polypropylene (PP) fiber surfaces by argon plasma irradiation, and surface‐modified PP fibers (PP‐g‐St fibers) were prepared by in situ grafting reaction of styrene monomers (St). The prepared samples were characterized by Fourier transform infrared, NMR, X‐ray photoelectron spectroscopy, scanning electron microscopy, and thermogravimetric analysis. Effects of reaction parameters on grafting percentage were studied, and adsorption capacities of PP‐g‐St fibers for benzene, toluene, and xylene (BTX) were evaluated. Regeneration adsorption efficiencies after adsorption of pure BTX and BTX emulsion and solution in water were explored. The results indicated that, using pure St as the monomer, the optimum input power, irradiation time, and grafting reaction time are 90 W, 3 min, and 3 h, respectively, and the grafting percentage of St reached 5.7% when pure St was used. The characterization results demonstrated that St was grafted onto the surface of the PP fibers. Compared to pristine PP fibers, the adsorption capacities of PP‐g‐St fibers toward toluene and xylene emulsions and solutions in water increased. In addition, regeneration adsorption efficiencies of modified fibers remained >90% after six cycles of regeneration adsorption experiments, which showed excellent regeneration ability. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46171.  相似文献   

18.
苯乙烯在MBS中的结合方式对PVC/MBS性能的影响   总被引:4,自引:0,他引:4  
以乳液聚合法合成了化学组成恒定的具有核-壳结构的(甲基丙烯酸甲酯/丁二烯/苯乙烯)共聚物(MBS),通过改变原料及其配比,使苯乙烯(St)在MBS中以共聚或接枝方式结合,用动态力学热分析仪研究了MBS内耗与温度的关系。将MBS与聚氯乙烯(PVC)共混,研究了St结合方式对共混物冲击韧性及增韧机理的影响,结果表明,随着MBS核中St含量的增加,PVC/MBS共混物的脆-韧转变向高温移动;当St仅以接枝的方式结合时,橡胶粒子的空洞化及剪切屈服是主要的增韧机理,当St仅以共聚方式结合时,剪切屈服是主要的增韧机理。  相似文献   

19.
采用苯乙烯(St)和N-苯基马来酰亚胺(NPMI)通过溶液共聚法制得(St/NPMI)共聚物。将(St/NPMI)共聚物和(丙烯腈/丁二烯/苯乙烯)共聚物(ABS)胶粉分别与ABS树脂进行熔融共混后挤出、切粒。结果表明,与ABS胶粉相比,(St/NPMI)共聚物能较好地提高ABS树脂的维卡热变形温度。  相似文献   

20.
按一定的次序将单体马来酸酐(MAH)、苯乙烯(St)、引发剂过氧化二异丙苯(DCP)、聚丙烯(PP)、废胶粉等在高速混合机中混合均匀后,在双螺杆挤出机中就地反应增容制备 PP/胶粉共混材料。讨论了 MAh/St/DCP 三者的含量对 PP/胶粉共混材料力学性能的影响;红外光谱(FTIR)分析证明双单体成功接枝于 PP 大分子链中。通过扫描电镜分析了一步法反应增容对 PP/胶粉共混物界面的影响。结果表明,一步法反应增容改善了共混物的界面相容性,当 PP、胶粉、DCP、MAH、St 的配比为70/30/0.1/1.5/1.5时,PP/胶粉共混物的拉伸强度和悬臂梁缺口冲击强度达到最佳。  相似文献   

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