Solution copolymers, butyl

Of the amorphous block copolymers, styrenic block copolymers are the vast majority. These are synthesized anionically in solution, with butyl lithium commonly employed as the initiator [4]. There are three processes for this polymerization ... 

Product Identification was by GC/MS, NMR, and IR. Fundamental crosslinking chemistry was explored using swell measurements on simple solution copolymers and swell and tensile measurements with vinyl acetate (VAc), vinyl acetate/butyl acrylate (VAc/BA) or vinyl acetate/ethylene (VAE) emulsion copolymers. Polymer synthesis 1s described In a subsequent paper (6). Homopolymer Tg was measured by DSC on a sample polymerized In Isopropanol. Mechanistic studies were done 1n solution, usually at room temperature, with 1, 2 and the acetyl analogs 1, 2 (R =CH3). 

Butvl Acrylate (BAl Solution Copolymers. Polymerizations were run with 0.30 mmol of comonomer per calculated g of polymer solids premixed with BA Reactor Charge X g comonomer, (50-X) g of butyl acrylate, 120 g of dry toluene, 0.15 g of 2,2 -azob1s1sobutyron1tr11e (AIBN). 

Figure 2. Medium-dependence of the rate of ds-trans isomerization of copolymer ABA-MMA. , dilute solution in butyl acetate A, polymer in btdk O, polymer plasticized with 30% DOF.

In all cases the data fit the models equally well. The data is summarized in Table VII. The plots of the data and the line of fit are in Figures 8 through 13. In the case of the solution copolymers, the extrapolated Tg values for butyl acrylate and vinyl acetate agree reasonably well with typical literature values of -54°C and 32 C, respectively [12], However, there is a wide variation in the values determined for... 

Polybutenes have heen used for almost a century and while they are still used, most of this type sealant contains butyl rubber, which is a copolymer of butene and isoprene. Most building specifications, including Federal Specification, TT-S-001637, require solutions of butyl rubber instead of oil-based caulking compositions. Self curing butyl rubber sealants may contain phenolic resins,IS. resorcinol and hexamethylenetetramine. ... 

Oleyl hydroxyethyl imidazoline PEG-5M PEG-7M PEG-14M Polyacrylamide flocculant, anionic water treatment Acrylamide/sodium acrylate copolymer flocculant, aq. systems Poly [oxyethylene (dimethyliminio) ethylene (dimethyliminio) ethylene dichloride] flocculant, aq./fatty food-contact paper/paperboard Polyquaternium-6 flocculant, boiler treatment Sodium nitrite flocculant, bonding agents Acrylamides copolymer flocculant, borine-contg. solutions t-Butyl hydroperoxide flocculant, car wax emulsions Oleyl hydroxyethyl imidazoline flocculant, carpet backings Acrylamides copolymer flocculant, cement Polyacrylamide flocculant, ceramic treatment PEG-5M PEG-9M PEG-23M PEG-45M... 

Figure 2. Thermal cis-trans isomerization of methyl methacrylate copolymer with 0.9 mole % of p-(N-methacrylyl)aminoazobenzene at 60 C after photochemical trans-cis isomerization at the same temperature (zr. )bulk polymer, (O)polymer plasticized with 30% dioctyl phthalate,( )dilute solution in butyl acetate.

Figure 19 Effects of monomer and grafting method on morphological structures of cotton-cellulose copolymers, as shown by electron microphotographs of fibrous copolymer cross-sections (a) immersion of cellulose in solution of styrene in methanol then high-energy IR radiation (b) immersion of cellulose in solution of vinyl acetate in 70% aqueous ZnClj then high-energy irradiation (c) immersion of cellulose in aqueous solution of butyl methacrylate then high-energy irradiation.

The low vinyl acetate ethylene—vinyl acetate copolymers, ie, those containing 10—40 wt % vinyl acetate, are made by processes similar to those used to make low density polyethylene for which pressures are usually > 103 MPa (15,000 psi). A medium, ie, 45 wt % vinyl acetate copolymer with mbber-like properties is made by solution polymerisation in /-butyl alcohol at 34.5 MPa (5000 psi). The 70—95 wt % vinyl acetate emulsion copolymers are made in emulsion processes under ethylene pressures of 2.07—10.4 MPa (300—1500 psi). 

Park et al. [20] reported on the synthesis of poly-(chloroprene-co-isobutyl methacrylate) and its compati-bilizing effect in immiscible polychloroprene-poly(iso-butyl methacrylate) blends. A copolymer of chloroprene rubber (CR) and isobutyl methacrylate (iBMA) poly[CP-Co-(BMA)] and a graft copolymer of iBMA and poly-chloroprene [poly(CR-g-iBMA)] were prepared for comparison. Blends of CR and PiBMA are prepared by the solution casting technique using THF as the solvent. The morphology and glass-transition temperature behavior indicated that the blend is an immiscible one. It was found that both the copolymers can improve the miscibility, but the efficiency is higher in poly(CR-Co-iBMA) than in poly(CR-g-iBMA),... 

By employing anionic techniques, alkyl methacrylate containing block copolymer systems have been synthesized with controlled compositions, predictable molecular weights and narrow molecular weight distributions. Subsequent hydrolysis of the ester functionality to the metal carboxylate or carboxylic acid can be achieved either by potassium superoxide or the acid catalyzed hydrolysis of t-butyl methacrylate blocks. The presence of acid and ion groups has a profound effect on the solution and bulk mechanical behavior of the derived systems. The synthesis and characterization of various substituted styrene and all-acrylic block copolymer precursors with alkyl methacrylates will be discussed. 

Figure 3. Time dependence of the fraction R of unreacted aminostyrene residues during acetylation by 0.14 M acetic anhydride at 30°C. Methyl methacrylate copolymer in acetonitrile solution (0) linear poly-(methyl methacrylate-co-butyl methacrylate) swollen with acetonitrile Cd) methyl methacrylate copolymer crosslinked with 1 mole% ( ) and with 15 mole% ( ) ethylene dimethacrylate poly(methacrylate crosslinked with 3 mole% ethylene dimethacrylate containing entrapped poly(methyl acrylate-co-aminostyrene) ( ).

Copolymers of tri-n-butylstannyl acrylate with alkyl acrylates (methyl, athyl, butyl or octyl acrylates) or acrylonitrile can be obtained in solution or in a slurry... 

GTP was employed for the synthesis of block copolymers with the first block PDMAEMA and the second PDEAEMA, poly[2-(diisopropylamino)e-thyl methacrylate], PDIPAEMA or poly[2-(N-morpholino)ethyl methacrylate], PM EM A (Scheme 33) [87]. The reactions took place under an inert atmosphere in THF at room temperature with l-methoxy-l-trimethylsiloxy-2-methyl-1-propane, MTS, as the initiator and tetra-n-butyl ammonium bibenzoate, TBABB, as the catalyst. Little or no homopolymer contamination was evidenced by SEC analysis. Copolymers in high yields with controlled molecular weights and narrow molecular weight distributions were obtained in all cases. The micellar properties of these materials were studied in aqueous solutions. 

Fig. 51 Phase diagram for PS-PI diblock copolymer (Mn = 33 kg/mol, 31vol% PS) as function of temperature, T, and polymer volume fraction, cp, for solutions in dioctyl ph-thalate (DOP), di-n-butyl phthalate (DBP), diethyl phthalate (DEP) and M-tetradecane (C14). ( ) ODT (o) OOT ( ) dilute solution critical micelle temperature, cmt. Subscript 1 identifies phase as normal (PS chains reside in minor domains) subscript 2 indicates inverted phases (PS chains located in major domains). Phase boundaries are drawn as guide to eye, except for DOP in which OOT and ODT phase boundaries (solid lines) show previously determined scaling of PS-PI interaction parameter (xodt

The poly(vinylpyridine) and poly(tert-butyl methacrylate) copolymers can easily be converted to either cationic or anionic polyelectrolytes by protonation of the pyridine rings or by base hydrolysis of the tert-butyl ester units, respectively. The highly branched structure of the molecules, in combination with the polyelectrolyte effect, should confer useful properties to these materials in solution for applications such as pH-sensitive reversible gels. 

The use of simultaneous equations with at least three sets of experimental data can, however, be applied to Eq. (101) or (102) to yield M, MA and MB. This is especially useful, if the specific co-ordinates of the whole parabola cannot be realised experimentally as is often the case. The data159-1 in Table 14 relate to a random copolymer of styrene (A)/di-n-butyl itaconate (B) in which WA = 0.169. Solution of simultaneous equations [Eq. (101)] yields M = 67300, MA = 56800 and MB =64700. The compositional heterogeneity is such that the data conform to the required theoretical relationship149 ... 

Figure 5. Lower Critical Solution Temperatures of Copolymers of N-isopropyl Acrylamide and N-n- and N-t-butyl Acrylamide as a Function of Monomer Input Ratios.

Figures 6 and 7 illustrate the preposed mechanism in OC. Using the specific example of a separation of a styrene n-butyl methacrylate copolymer, the first SEC separates the copolymer according to molecular size in solution. At any desired retention time, the flow in the first instrument is stopped and an injection made into the second instrument of a single molecular size "slice" of the chrcoiatogram. The solvent running in the second instrument is a mixture of tetrahydrofuran (THF) and n-heptane. THF is a solvent for both styrene cuid n-butyl methacrylate portions of the polymer molecules. However, n-heptane is a nonsolvent for the styrene-rich portions. As a result, vrfien the injection is made into the second instrument, the styrene-rich molecules will shrink relative to the n-butyl methacrylate-rich molecules. An immediate size distribution will be present vrfiich will reflect the composition differences. The smaller styrene-rich molecules will enter more pores of the column packing than their n-butyl methacrylate-rich counterparts and so be fractionated. Furthermore, since the styrene-rich molecules "hate" the mobile phase, they should find the surface area of the packing more "sticky" than the n-butyl methacrylate-rich molecules. Thus, again the styrene-rich molecules should be retarded relative to the others. According to this picture, the mechanisms of size exclusion, adsorption and partition are thus able to act synergistic ally to accomplish a composition separation.

Rubber-toughened polystyrene composites were obtained similarly by polymerising the dispersed phase of a styrene/SBS solution o/w HIPE [171], or a styrene/MMA/(SBS or butyl methacrylate) o/w HIPE [172], The latter materials were found to be tougher, however, all polymer composites had mechanical properties comparable to bulk materials. Other rubber composite materials have been prepared from PVC and poly(butyl methacrylate) (PBMA) [173], via three routes a) blending partially polymerised o/w HIPEs of vi-nylidene chloride (VDC) and BMA, followed by complete polymerisation b) employing a solution of PBMA in VDC as the dispersed phase, with subsequent polymerisation and c) blending partially polymerised VDC HIPE with BMA monomer, then polymerisation. All materials obtained possessed mixtures of both homopolymers plus some copolymer, and had better mechanical properties than the linear copolymers. The third method was found to produce the best material. 

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