Radical polymerization of new functional monomer: methacryloyl isocyanate containing 3-chloro-1-propanol

A new functional monomer, methacryloyl isocyanate, containing 3-chloro-1-propanol (CPL-MAI), was prepared in a reaction of methacryloyl isocyanate (MAI) with 3-chloro-1-propanol (CPL) at low temperature and was characterized by IR, ¹H and ¹³C NMR spectra. Radical polymerization of CPL-MAI was studied in terms of the rate of polymerization, solvent effect, copolymerization, polymer modification and thermal properties. The rate of polymerization of CPL-MAI has been found to be smaller than that of styrene under the same conditions. Copolymerization of CPL-MAI (M₁) with styrene (M₂) in tetrahydrofuran (THF) was studied at 60°C. The monomer reactivity ratio was calculated to be r₁=0.26 and r₂=0.33 according to the method of Fineman–Ross. Poly(CPL-MAI) was easily modified by reacting with the sodium salt of carbazole leading to a displacement of 49% conversion. The TG curve for poly(CPL-MAI) is in two stages and shows two maxima peaks at 206 and 416°C.     

Radical polymerization of methacryloyl isocyanate containing 1-adamantanol

Summary Radical polymerization of the methacryloyl isocyanate containing 1-adamantanol (Ad-MAI) with AIBN in different solvents at 60°C was investigated. It is observed that polymerization is slower in polar solvents than in nonpolar ones. The rate of polymerization for Ad-MAI was found to be slower than those of Adph-MAI and MMA both in photopolymerization and in thermal polymerization. Copolymerization of Ad-MAI (M₁) with styrene (M₂) in benzene was studied at 60°C. The monomer reactivity ratio was calculated to be r₁=1.53 and r₂=0.76 according to the method of Fineman-Ross. The prominent glass transition temperature for poly(Ad-MAI) was observed at 142°C from global TSC spectrum. Received: 20 November 1998/Revised version: 16 February 1999/Accepted: 25 February 1999     

含亲水性丙烯酸酯单体的微乳液聚合研究

在构建含亲水丙烯酸酯单体微乳液聚合体系的基础上,描绘了微乳液体系的拟三元相图,考察了乳化剂和助乳化剂类型对微乳液相行为的影响,并进行了该体系正相微乳液聚合。结果表明正戊醇、环己醇、乙醇等作为助乳化剂协同阴离子乳化剂十二烷基硫酸钠(SDS)可以形成稳定的单相微乳液,但是这些微乳液体系在聚合过程中很容易生成凝胶;环己烷作为助乳化剂虽然在配制过程中不能形成稳定的透明或半透明体系,但是在反应过程中则比较稳定,能形成半透明状的聚合物微乳液;阴离子乳化剂与其它非离子乳化剂组合以及单独使用非离子乳化剂均难以制备稳定的微乳液。     

Radical polymerization of mono- and di-methacrylic esters containing bisphenol-S

Radical polymerizations of mono- and di-methacrylic esters containing bisphenol-S (BPS-M and BPS-DM) were studied in terms of polymerization rate, solvent effect, copolymerization and kinetic measurements of photocrosslinking. The solvents were found to affect significantly the polymerization rate. Polar solvents such as DMSO and acetonitrile were found to slow down the polymerization rate. Copolymerization of BPS-M(M₁) with MMA(M₂) was studied in acetone at 60°C. The monomer reactivity ratios were calculated to be r₁ = 3.72 ± 0.01 and r₂ = 0.80 ± 0.01 by the Fineman-Ross method. The high reactivity of BPS-M observed in this copolymerization system may be due to the “matrix effect”. Functional polymers containing methacrylate side-groups were successfully modified and photocrosslinked by irradiation in the presence of benzoin isopropyl ether. The photocrosslinking process is found to be of second order kinetics.     

Preparation and polymerization of vinyl monomers containing a heterocyclic pendant group

New vinyl monomers having an isoxazole heterocyclic group were synthesized and were polymerized in dimethylformamide using azobisisobutyro-nitrile as a free radical initiator. The dependence of the rate of polymerization on monomer and initiator concentrations was determined, as well as the activation energy of polymerization. The addition of Lewis acid was found to affect the rate of polymerization. The prepared monomers were copolymerized with styrene, vinyl acetate, acrylonitrile and methyl methacrylate. The monomer re-activity ratios of all the systems were determined by linear and non-linear methods, and the Q and e values for the monomers were calculated by considering the four copolymerization systems in each case. ©1997 SCI     

Synthesis and polymerization of new multifunctional pyrrolidinone methacrylate monomers

Methacrylate monomers have been widely used in medical and dental applications such as bone cements, dental fillings, bioadhesives, and hydrogels. One major problem of these monomers resides in their low rates of polymerization leading to leaching problems that cause irritation of the surrounding tissues and even cell death. Here we describe the synthesis and polymerization of new mono-methacrylates containing multifunctional pyrrolidinone moieties. Such monomers possess stronger inherent hydrogen bonding potential susceptible to increase their reactivity and polymerization rates. These monomers were shown to homopolymerize rapidly leading to crosslinked polymers. The corresponding rates of polymerization were found to be comparable to difunctional methacrylates such as hexanediol dimethacrylate. Intermolecular hydrogen bonding interactions involving the pyrrolidinone unit leads these monomers to behave as “pseudo” difunctional monomers upon homopolymerization.     

Radical polymerization of fluoroalkyl 2-fluoroalkoxy methacrylate to new type of fluorine containing polymer

Summary Fluoroalkyl 2-fluoroalkoxymethylacrylates as 1,1-disubstituted ethylenic monomers were synthesized from methyl 2-hydroxymethylacrylate as a starting compound. These monomers readily polymerized to high molecular weight despite considerable steric hindrance expected. Electron withdrawing character of the fluoroalkyl groups rendered these monomers as much stronger electron accepting monomers than methyl methacrylate in copolymerization. The polymers obtained were characterized by thermal stability, glass transition temperature, and contact angle of the polymer film to water.     

Pressure sensitive adhesives of acrylic polymers containing functional monomers

Pressure sensitive adhesives possessing good cohesive strength have been prepared by copolymerizing n-butyl acrylate with various functional monomers. The effect of the polar nature and of the concentration of comonomer on tack, adhesion and cohesion was studied. The cohesive strength of the adhesive was determined on various surfaces. A comparative study was made to assess the effectiveness of a particular comonomer on the basis of the results obtained.     

Radical polymerization of fumaramide and fumaramate derivatives for homogeneous Langmuir monolayers

Summary The radical polymerization of a series of fumaramides and fumaramates, prepared from the reaction of various amines with fumaroyl dichloride and fumaric chloride isopropyl ester, respectively, was investigated. Although the polymerization reactivity of the N,N,N’,N’-tetrasubstituted fumaramides and N,N-disubstituted fumaramates was low, N-isopropyl fumaramate readily furnished the corresponding high molecular weight polymer. The highest number average molecular weight (M_n) of 15,400 was obtained from the emulsifier-free emulsion polymerization in the presence of VA-086 as the initiator. The decomposition temperature of the obtained polymer was determined to be 299 °C. The π-A isotherm of the polymer indicated the formation of stable Langmuir monolayers with a limiting molecular area (per macromolecular repeating unit) of ca. 26 ?².     

带双甲基丙烯酰基偶氮苯液晶化合物的合成与表征

合成了一毓新的带双甲基丙烯酰基偶氮苯液晶化合物,并利用元素分析、红外光谱、核磁共振谱及热台偏光显微镜等方法对其进行了不征。     

Forgotten monomers: free radical polymerization behavior of norbornadiene derivatives in comparison with methyl methacrylate

The free radical polymerization behavior of three norbornadiene derivatives was studied as a function of their structure. The compounds examined were 3-ethoxycarbonyl-tricyclo[3.2.1.0^2,4]oct-6-ene 1 (liquid), 2-carbethoxybicyclo[2.2.1]-2,5-heptadiene 2 (liquid) and 2-carboxybicyclo[2.2.1]-2,5-heptadiene 3 (solid). They were polymerized in bulk and in benzene solutions. The tricyclic compound 1 was the least reactive monomer whereas the bicyclic derivatives 2 and 3 readily polymerized radically to high conversions. The corresponding polymers were isolated and their structure were determined by means of IR- and NMR spectroscopy. The polymerization of 3-ethoxycarbonyl-tricyclo[3.2.1.0^2,4]oct-6-ene 1 is supposed to proceed through a simultaneous ring opening-ring closing mechanism. The corresponding polymer poly-1 shows low molecular weights. The polymerization results were compared with those obtained for a conventional solution polymerization of methyl methacrylate.     

Atom transfer radical polymerization of monomers containing amide and ester moieties monitored by dilatometric method

The kinetics of atom transfer radical polymerization of N-(S)-α-methylbenzylmethacryloylamine (S-(-)-α-MBMA) and α-methylbenzylmethacrylate (α-MBM) monomers, as assessed by % conversion, were determined at 48 °C in a toluene/ethanol mixture (60:40) by a dilatometry method. The effect of the presence of — CONH- or — COOR- moieties on the ATRP polymerization of such monomers was investigated. Controlled polymerizations were performed with the catalyst system [ M ]/[ R - X ]/[ Mtⁿ - Y ]/[ L ] \left[ {\hbox{M}} \right]/\left[ {{\hbox{R}} - {\hbox{X}}} \right]/\left[ {{\hbox{M}}{{\hbox{t}}^{\rm{n}}} - {\hbox{Y}}} \right]/\left[ {\hbox{L}} \right] at molar ratios of 100:15:15:15; 200:15:15:15; 300:15:15:15; and 400:15:15:15, where R-X was EBIB or MCP, M_tⁿ-Y(CuBr or CuCl) and L (Me₆TREN). Also with N-S-(-)-α-MBMA, some studies used ATCA and ABPA as R-X. Plots of the ln[M]₀/[M] vs t as well as from the log Rp vs log [M] showed that the ATRP processes followed a pseudo first-order kinetics with respect to the monomer concentration and that the molecular weight of the resulting polymers increased with the conversion. The ATRP results for both monomers showed a similar trend and revealed that the presence of N-S-(-)-α-MBMA (amide group) affects the polymerization, i.e. it did not react when the EBIB/CuBr/Me₆TREN catalyst system was used. The M_n and M_w were determined by ¹H-NMR and GPC. PDI values fell between 1.19 and 1.5, and indicated that the majority of the systems showed good control of polymerization.     

Electroinitiated polymerization of butyl isocyanate: 2. Polymerization kinetics

Electrolysis of a solution of a quaternary ammonium perchlorate or tetrafluoroborate produces a transient species capable of polymerizating n-butyl isocyanate: some direct reduction of the monomer also occurs. High molecular weight polymer is produced during the early stages of the reaction, and small but measurable quantities of cyclic trimer are formed during the later stages. Kinetic analysis of the polymerization indicates a complex reaction mechanism; above a certain current density the overall rate of reaction appears to be zero order in current. The rate also shows an unusual acceleration and appears to depend on the quantity of monomer already consumed.     

Synthesis and polymerization of new vinyl derivatives of thymine

N-acryloyl and N-methacryloyl derivatives of thymine were prepared by one-step reaction of silylated thymine with acryloyl chloride and methacryloyl chloride, respectively, in good yields. These vinyl monomers containing thymines were polymerized and copolymerized with water soluble vinyl monomers such as acrylamide and vinylpyrrolidone by free-radical polymerization. Complex formation between copolymers and RNA in aqueous solution was studied by means of UV spectroscopy.     

Tyrosine imprinted polymer beads with different functional monomers via seed swelling and suspension polymerization

Molecularly imprinted polymers (MIPs) in bead form were prepared by seed swelling and suspension polymerization with trimethylolpropane trimethacrylate (TRIM) as crosslinker and tyrosine as template. The appearance of the beads was found to be greatly influenced by the concentration of polyvinyl alcohol (PVA) used as dispersant and the ratio of water to TRIM (W/T) during polymerization. When W/T was 46:1 (V/V) and the concentration of PVA‐water solution was 4.6 (%m/m), the result was more desirable size distribution with fewer misshapen beads. A series of imprinted polymers with methacrylic acid (MAA), acrylamide (AM), 2‐vinylpyridine (VP) and 2‐acrylamido‐2‐methylpropanesulfonic acid (AMPS) as functional monomers (FM), respectively, were prepared, where the molar ratio of tyrosine, FM and TRIM was chosen as 1:16:17. The molecule adsorbing and selecting analysis of the polymers showed that although all the imprinted polymers adsorbed the templates following the rule of Langmuir and exhibited an obvious molecule selecting capability compared with their control polymers (CP), the adsorbing constant and the separating factor were much different when the functional monomers varied. AMPS worked better than the other FM in the present work with a higher value of asymptotic maximum solid phase concentration (0.282 mol/kg), adsorbing constant (198.81/mol), and a larger separating factor (1.93) when phenylalanine was used as the competitive molecule.     

Electroinitiated polymerization of some new monomers with schiff's base structure and pyrrole moieties

Pyrrole-2-aldehyd azine, N,N'-bis(2-pyrrolylmethylene)-1,4-diaminobenzene and N,N'-bis(2-pyrrolylmethylene)-4,4′-diaminobiphenyl were polymerized by electro-chemical precipitating oxidation reaction in 1,2-dichloroethane and acetonitrile, respectively, in the presence of electrolytes like tetrabutylammonium perchlorate, tetrabutylammonium tetrafluoroborate and sodium p-toluene sulfonate. The doped resulted polymers were characterized by elemental analysis, IR spectroscopy and thermal analysis.     

Radical polymerization of styrene initiate with a new multifunctional iniferter

Summary A new multi-functional iniferter with photo-induced and thermal dissociation group in one molecule, diethyl 2,3-dicyano-2,3-di(p-N,N-diethyldithiocarbamylmethyl)phenylsuccinate(DDDCS), was successfully synthesized. The bulk polymerizations of styrene (St) with DDDCS were studied. The initiation can take place either under UV light irradiation by the reversible C-S bonds dissociation of DDDCS or under heating by the reversible hexa-substituted C-C bond thermally dissociation. The polymerizations have "living" polymerization characteristics under both cases, i.e., the yield and the molecular weight of the resulting polymer increased linearly with increasing reaction time, and the resultant polymers can act as macroiniferter for preparing block copolymer. Received: 5 December 1999/Revised version: 17 January 2000/Accepted: 21 January 2000     

Multistage melt polymerization of bisphenol-A and diphenyl carbonate to polycarbonate

A multistage melt polycondensation of bisphenol-A and carbonate has been studied experimentally using LiOH·H₂O catalyst. The reaction process consists of batch and semi-batch periods with different temperature and pressure conditions. It was observed that a small amount of diphenyl carbonate lost from the reaction mixture by vaporization had little effect on the molecular weight in the batch reaction period but the efficiency of subsequent low-pressure semibatch polycondensation was affected by the change in the mol ratio of the phenyl carbonate group to the hydroxyl end group. A molecular species model developed for the multistage process was used to analyze the kinetics of the polycondensation process. The composition of the reaction mixture was analyzed of HPLC and compared with model simulations. In particular, the effect of evaporative loss of diphenyl carbonate on the progress of reaction is discussed in detail. © 1993 John Wiley & Sons, Inc.     

Synthesis of chemically amplified photoresist polymer containing four (Meth)acrylate monomers via RAFT polymerization and its application for KrF lithography

KrF photoresist polymers (PASTMs) were prepared via reversible addition-fragmentation chain transfer (RAFT) polymerization. Four (meth)acrylates with lithographic functionalities including styrene (St), 4-acetoxystyrene (AST), 2-methyl-2-adamantyl methacrylate (MAMA), and tert-butyl acrylate(TBA) were used as monomer components and 2-methyl-2-[(dodecylsulfanylthiocarbonyl) sulfanyl]propanoic acid (MDFC) was used as RAFT agent, varying the RAFT content could modulate molecular weight. Fourier-transform infrared spectroscopy (FT-IR) and proton nuclear magnetic resonance (¹H NMR) indicated that the synthesis was successful. Gel permeation chromatography (GPC) showed that the molecular weight decreased with the increased content of MDFC, and all the polymers possessed weight-average molecular weight below ten thousand and polydispersity less than 1.32. Thermogravimetric analysis (TGA) characterized the thermal properties, the results implied that initial thermal decomposition temperature reached 200 °C, which could satisfy the lithography process. Differential scanning calorimetry (DSC) showed that the Tg decreases with molecular weight. The RAFT polymerization kinetics plots demonstrated that the polymerization was first-order, the number-average molecular weights of the polymers with relatively low polydispersity index values increased with total monomer conversions indicating that the concentration of growing radicals was constant throughout the polymerization process. The narrow molecular weight distribution and composition uniformity of the polymers prepared by RAFT polymerization could be beneficial for lithography, after alcoholysis, lithography evaluation under KrF lithography showed that this homogeneous polymer photoresist exhibited better space and line (S/L) pattern with resolution of 0.18 μm according to the SEM image.     

Solid-state polymerization of derivatives of 2,4,6-octatriyne: 9. Topochemical reactions of monomers with conjugated triple bonds

The solid-state polymerization of monomers with three conjugated triple bonds gives rise to polymer single crystals. The lattice parameters of the polymers from 2,4,6-octatriyne-1,8-diol and 2,4,6-octatriyne-1,8-diol-bis(phenyl urethane) were determined. Based on these data and considering the mechanical properties and dichroism of the polymer crystals, it is concluded that polymerization proceeds according to a 1,4-addition to the triple bond system of the monomers. Only two of the three triple bonds of the monomers are affected by polymerization to form the polymer backbone of regularly alternating double, single and triple bonds. The residual triple bond is regularly arranged in the all-trans position as part of the substituents. The kinetics of the thermal and photopolymerization of these monomers are quite similar to those of the corresponding diynes. The activation energy of thermal polymerization was found to be 23 kcal/mol as compared to 19 kcal/mol for comparable diynes. The long wavelength limit of photosensitivity was found to be at about 380 nm as compared to 330 nm for diynes.