Methacryl-terminated macromers by living polymerization as precursors of IPN polymer electrolytes

A new class of polymer electrolytes, based on the interpenetrating polymer network approach, was obtained starting from functionalised macromers, of poly-ether nature, in the presence of a lithium salt (LiBF₄, LiClO₄, LiCF₃SO₃) and propylene carbonate (PC) or tetraethyleneglycol dimethylether (TGME), as plasticizers.

The macromers were synthesised by living polymerisation employing a HI/I₂ system as the initiator. The macromer has a polymerisable end group, which can undergo radical polymerisation, attached to a monodisperse poly-vinylether, containing suitable ethylene oxide groups for ion coordination. Monomers and macromers were characterised by FTi.r., u.v.–vis, ¹H- and ¹³C-n.m.r.

Self-consistent and easily handled membranes were obtained as thin films by a dry procedure using u.v. radiation to polymerise and crosslink the network precursors, directly on suitable substrates, in the presence of the plasticizer and the lithium salt. The electrolytic membranes were studied by complex impedance and their thermal properties determined by differential scanning calorimetry analysis.

Ionic conductivities (σ) were measured for PC and TGME-based membranes at various plasticizer and salt contents as a function of T (60 to −20°C). LiClO₄/PC/PE electrolytes, with 3.8% (w/w) salt and 63% PC, have the highest σ (1.15×10⁻³ and 3.54×10⁻⁴ S cm⁻¹ at 20°C and −20°C, respectively). One order of magnitude lower conductivities are achieved with TGME; samples with 6% (w/w) LiClO₄ and 45% (w/w) TGME exhibit σ values of 2.7×10⁻⁴ and 2.45×10⁻⁵ S cm⁻¹ at 20°C and −20°C.     

Synthesis of macromers of vinylchloride and vinylidene chloride from telomers

New macromers are prepared from monofunctional telomers of vinylidene chloride and vinylchloride obtained by redox catalysis or by means of radical initiators. Especially, model graft copolymers are obtained upon copolymerising these telomers with acrylic compounds.     

半连续乳液聚合法制备高支化聚甲基丙烯酸甲酯

以甲基丙烯酸甲酯(MMA)为单体、二乙烯基苯(DVB)为支化剂和十二硫醇(C12SH)为链转移剂,采用半连续乳液聚合法制备了一系列低凝聚率高支化的PMMA(聚甲基丙烯酸甲酯)。着重探讨了不同单体配比对该乳液的稳定性、支化度(DB)、玻璃化转变温度(Tg)、相对分子质量及其分布等影响。结果表明:高支化PMMA乳液的粒径较小、粒径分布较窄;当n(DVB):n(C12SH)=1:2时,DVB和C12SH总用量越多[或当n(MMA):n(DVB)=100:10时,C12SH用量越多],聚合物的DB越高、相对分子质量越小、相对分子质量分布越窄且Tg越低。     

Synthesis of hydroxy-functionalized star-branched PMMA by anionic polymerization

Living anionic polymerization has been exploited to synthesize hydroxy end-functionalized PMMA star-branched polymers. Protected hydroxy-functionalized alkyl lithium initiators have been used to initiate anionic polymerization of MMA. Subsequently the living chains with protected hydroxyl function have been used to cross-link ethylene glycol dimethacrylate (EGDMA) in order to form star-branched polymers with cross-linked EGDMA core via ‘arm-first’ method. The linear arms and the star molecules have been characterized by ¹HNMR, GPC, and light scattering. Variation in the number of arms with arm molecular weight and cross-linker loading has been studied. Star-branched PMMA-OH with as many as ~10 arms could be successfully made. Increased molecular weight of PMMA-OH led to decrease in the number of arms incorporated due to increased steric hindrance on the core. Increase in EGDMA concentration slightly increased the arm incorporation.     

Preparation of encapsulated aluminum pigments by emulsion polymerization and their characterization

An emulsion polymerization-like process for the encapsulation of commercial aluminum pigments with polymer is discussed. A possible application target is the improvement of the performance of aluminum pigment in waterborne coatings. The effect of the treatment on the stability of the aluminum pigments in the presence of alkaline water was examined. Analytical investigations with SEM, TEM, STEM-EDX, XPS, and TOC were performed and revealed a kind of coagulation mechanism of polymer particles on the pigment surface. D-63784 Obernburg, Germany.     

纳米硅基氧化物改性有机玻璃的制备及表征

以甲基丙烯酸甲(MMA),内米级硅基氧化物（nSiO)等为原料，使用特殊的工艺和新开发的助剂，采用原位加成聚合，制备了PMMA／nSiO复合材料。复合材料的冲击性能提高超过40％，维卡热变形温度提高15℃以上，可见光透过度88．1％，下降很少。     

浸润剂的制备及对3D打印产品力学性能的影响

以环氧树脂和丙烯酸酯类单体为主要原料制备了两种用于3D打印产品的浸润剂。用两种浸润剂和石蜡对3D打印的聚甲基丙烯酸甲酯(PMMA)试样进行了处理,研究了浸润剂对PMMA力学性能的影响。结果表明,反应型浸润剂对选择性激光烧结和喷墨砂型打印的产品有明显的增强作用,环氧浸润剂处理的产品经后处理后力学性能优于丙烯酸浸润剂处理的产品,黏度对环氧浸润剂的增强效果有较大影响。     

Synthesis of triglyceride-based urethane macromers and their use in copolymerization

Triglyceride oil-based urethane macromer (TGU) containing vinyl double bond was synthesized by the reaction of partial glyceride mixture (PGM) and methyl vinyl isocyanate (MVI). Free radical polymerization and copolymerization of TGU was studied. The structure of the TGU and polymers were elucidated by gel permeation chromatography (GPC) analysis, Fourier transform infrared spectroscopy (FT-IR) and ¹H nuclear magnetic resonance (¹H NMR) spectral measurements. The film properties of polymers were investigated by water resistance, alkali and acid resistance and contact angle measurements.     

Preparation and application of low-molecular-weight poly(vinyl chloride). V. Preparation and characteristics of blended poly(vinyl chloride) by two-step suspension polymerization

Poly(vinyl chloride) (PVC) with relatively broader molecular weight distribution (BMD-PVC) was prepared by two-step suspension polymerization: (1) preparation of poly(vinyl chloride) with relatively higher molecular weight (HMW-PVC) and (2) successive preparation of poly(vinyl chloride) with relatively lower molecular weight (LMW-PVC) in the presence of the resultant HMW-PVC and 2-mercaptoethanol as a chain transfer agent. Some properties of BMD-PVC were investigated: fusion time, melt viscosity, discoloration time, tensile strength at yield, tensile modulus in tension, and elongation at break. © 1994 John Wiley & Sons, Inc.     

一种新型环保氯乙烯聚合引发剂的制备与应用

介绍了一种新型环保型氯乙烯聚合引发剂——过氧化新癸酸-1,1,3,3-四甲基丁酯(TOPND)的研制方法及其应用,提出了未来几年新型环保引发剂复配体系的发展趋势。     

Synthesis of oxyquinolyl end-functional PMMA by atom transfer radical polymerization

Abstract: Oxyquinolyl end group functionalized PMMA was prepared by a new initiator 5-chloromethyl-8-hydroxyquinoline via atom transfer radical polymerization. Studying this polymer, we find it possesses stronger fluorescence and larger nonlinear third-order optical (NLO) coefficient than the PMMA initiated by ethyl -bromoisobutyrate, and the polymer could be easily processed into film. The NLO coefficient of the polymer tested in the film is better than that in the solution.     

3,5-二氧基苯甲酰哌嗪和均苯三甲酰氯界面聚合法制备复合纳滤膜

A new aromatic diamine,3,5-diaminobenzoylpiperazine (3,5-DABP),was synthesized from 3,5-diaminobenzoic acid and 1-formyl piperazine.The structure of 3,5-DABP was identified by FT-IR spectra and 1H NMR spectra.With 3,5-DABP as aqueous monomer and trimesoyl chloride (TMC) as organic monomer,thin film composite (TFC) nanofiltration membranes were prepared by interfacial polymerization technology.The salt rejection order of these TFC membranes is Na2SO4>MgSO4>MgCl2>NaCl.This sequence indicates that the membranes are negatively charged.     

Preparation of high PMMA grafted particle SiO2 using surface initiated free radical polymerization

In this work, a convenient surface-initiated free radical graft-polymerization method, by which polymethacrylic acid (PMAA) with a high grafting density was grafted on silica gel particles, was put forward, and it was feasible and effective. The coupling agent γ-aminopropyltrimethoxysilane (AMPS) was first bound onto the surfaces of silica gel particles, obtaining the modified particles AMPS-SiO₂. So a redox initiation system was constituted with the amino groups on the surfaces of AMPS-SiO₂ particles and ammonium persulphate in the solution. A great deal of primary free radicals on the surfaces of AMPS-SiO₂ particles is produced via the redox initiating reaction, so that the surface-initiated free radical graft- polymerization of methacrylic acid (MAA) on the silica gel particles was realized, giving the grafted particles PMAA/SiO₂ with a high grafting degree (about 30 g/100 g) of PMAA. The effects of the main factors on the surface initiated graft polymerization were examined and the corresponding mechanism was investigated in depth. The experimental results show that for this surface-initiated free radical graft-polymerization of MAA, the suitable temperature is 40 °C. If the temperature is over 40 °C, the graft polymerization will be affected negatively, and the grafting degree of PMAA will decline because of the intense heat decomposition of ammonium persulphate. During the graft polymerization, the grafted polymer layer that has formed is a hindrance to the subsequent graft polymerization. The used amount of initiator and the monomer concentration affect the graft polymerization greatly. The appropriate reaction conditions are as follows: reaction time of 10 h, initiator persulphate amount of 1.1% (it implies the mass percent of the monomer), and monomer MAA concentration of about 5% (it drives at the mass percent of the solution).     

Preparation and characterization of a composite nanofiltration membrane from cyclen and trimesoyl chloride prepared by interfacial polymerization

A novel nanofiltration (NF) membrane was prepared with cyclen and trimesoyl chloride by interfacial polymerization on a poly(ether sulfone) ultrafiltration membrane with a molecular weight cutoff of 50,000 Da. The effects of the reaction time, monomer concentration, and heat‐treatment temperature are discussed. The physicochemical properties and morphology of the prepared NF membrane were characterized by Fourier transform infrared spectroscopy–attenuated total reflectance, scanning electron microscopy, energy‐dispersive spectrometry, and atomic force microscopy. The NF performances were evaluated with solutions of Na₂SO₄, MgSO₄, Mg(NO₃)₂, and NaCl. The salt‐rejection order of the prepared NF membrane was as follows: Na₂SO₄ > MgSO₄ > Mg(NO₃)₂ > NaCl. The resulting rejection of Na₂SO₄ and PEG600 (polyethylene glycol with the average molecular weight of 600) were more than 90%, whereas that of NaCl was approximately 10%. After the addition of silica sol in the aqueous phase (silica sol concentration = 0.1% w/v), the salt rejection of the membrane changed slightly. However, the water flux was from 24.2 L·m^?2·h^?1 (25°C, 0.6 MPa) up to 38.9 L·m^?2·h^?1 (25°C, 0.6 MPa), and the resulting membrane exhibited excellent hydrophilicity. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42345.     

氯乙烯悬浮聚合用ACR乳液及抗冲PVC树脂的制备

采用种子乳液聚合工艺制备了ACR乳液,并与氯乙烯悬浮聚合制备了抗冲PVC树脂,考察了种子单体配比对种子乳液粒径的影响,种子乳液用量对ACR乳液粒径的影响,ACR乳液粒径对抗冲PVC树脂性能的影响。结果表明:1由于共聚的2种种子单体的结构相近,因此其配比对种子乳液粒径影响不大;2采用不同种子乳液用量制得的ACR乳液,实测粒径与理论粒径相差在7 nm以内,表明ACR乳液的粒径是可控的;3ACR乳液的适宜粒径为(200±10)nm,此时PVC树脂的冲击强度得到大幅提升,拉伸强度略有下降,维卡软化温度基本不受影响;4该ACR乳液与氯乙烯悬浮聚合时没有粘釜问题。     

无皂乳液制备PMMA动力学及其模型

以甲基丙烯酸甲酯(MMA)为单体、过硫酸钾(KPS)为引发剂进行无皂乳液聚合反应,考察了单体MMA浓度、引发剂KPS用量及聚合温度对其动力学行为的影响。建立了转化率-时间关系曲线的模型函数———Gamm a积分函数,用它拟合了转化率-时间关系曲线,获得了聚合过程的重要特征参数,如平均成核速率,聚合最大速率和平稳期平均聚合速率及成核结束和聚合进入完成期对应的转化率。同时对聚合速率与以上各聚合参数的关系数据进行了非线性拟合,得到了它们之间的关系式。拟合相关系数非常接近于1,平均拟合误差很小,成核结束时转化率在15%以内,聚合速率随以上参数增大而增大,反应温度在聚合过程中起决定作用。     

Synthesis and friction properties of copper/PMMA composites by soapless emulsion polymerization

Copper (Cu)‐doped polymethylmethacrylate (PMMA) composites were prepared by soapless emulsion polymerization. In this process, copper nanoparticles were modified by sodium oleate (SOA) and the surface property of Cu nanoparticles changed from hydrophilic to hydrophobic. The hydrophobic Cu nanoparticles could not only avoid the oxidation of Cu in air but also improve the compatibility between Cu nanoparticles and PMMA. The TEM micrographs revealed that Cu nanoparticles were encapsulated in PMMA polymer microspheres. In addition, the uniform Cu/PMMA composite microspheres could be synthesized in such a soapless emulsion polymerization process. It was worth mentioning that the friction property in oil was well improved when little nanocomposites were added into the base oil, which indicated that the composites can be widely used in lubricating oil. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

原位乳液聚合聚苯胺/聚甲基丙烯酸甲酯复合物及其表征

以DBSA为乳化剂和掺杂剂,在水介质中采用原位乳液聚合法制备出了聚苯胺/聚甲基丙烯酸甲酯(PANI/PMMA)复合物。采用扫描电镜、红外光谱分析、紫外光谱分析、热失重分析、X射线光电子能谱分析对PANI/PMMA复合物进行了表征。结果表明:复合物产物粒径在80～120nm;电导率可达到10-2S/cm,接近于乳液聚合得到的DBSA掺杂态PANI;乳化剂DBSA以掺杂剂和稳定剂两种状态存在于复合物中。     

原位聚合法制备纳米ATO/PMMA乙醇分散液的研究

将纳米掺锑二氧化锡(ATO)粒子经过超声分散和偶联剂处理后,以甲基丙烯酸甲酯(MMA)为单体,用原位聚合法制备了纳米ATO/PMMA乙醇分散液。讨论了偶联剂种类、MMA与ATO质量比值、引发剂偶氮二异丁腈(AIBN)用量对纳米ATO/PMMA乙醇分散液分散稳定性的影响。确定了合适的偶联剂为乙烯基三叔丁基过氧硅烷(VTPS),最优工艺参数为m(MMA)∶m(ATO)=2,w(AIBN)=1.5%。往聚丙烯酸酯树脂加入该纳米ATO/PMMA乙醇分散液所制得的涂料,其涂膜同时具有良好的可见光透过率和近红外光阻隔性能。     

Preparation of gel polymer electrolytes using PMMA interpenetrating polymeric network and their electrochemical performances

A gel polymer electrolyte (GPE) is prepared from polymethylmethacrylate interpenetrating polymer network, benzoyl peroxide, and 1.1 M LiPF₆/EC-DEC (1:1 vol.%). The LiCoO₂/graphite cells are prepared and their electrochemical properties were evaluated at various current densities and temperatures. The viscosity of the precursor containing 5 vol.% curable mixture is around 4.6 mPa s. The ionic conductivity of the GPE at 20 °C is around 5.8×10⁻³ S cm⁻¹. The GPE has good electrochemical stability up to 4.8 V vs. Li/Li⁺. The capacity of the cell at 1.0C rate is 82% of the discharge capacity at 0.2C rate. The capacity of the cell at −10 °C is 86% of the discharge capacity at 20 °C. Discharge capacity of the cell with GPE is stable with charge-discharge cycling.