Reactive diluents were prepared from tung oil via a Diels–Alder reaction with three different dienophiles: methacryloxypropyl trimethoxysilane (TOMAS), 2,2,2-trifluoroethyl methacrylate (TOF) and triallyl ether acrylate (TOTAE). The reactive diluents were mixed with a long oil soya alkyd, a metal drier package, and a wetting agent; and then cured. Formulations were prepared as a function of reactive diluent type and wt%. Tensile, thermomechanical, and coatings properties were evaluated after curing the films. The addition of two reactive diluents, TOMAS and TOTAE, improved the tensile strength and tensile modulus of the alkyd. The addition of the diluents, however, did not significantly change the elongation at break compared to the alkyd in any of the systems. Also, the addition of TOMAS and TOTAE increased both the crosslink density and glass transition temperature of the alkyd. Basic film properties including hardness, solvent resistance, impact resistance, adhesion, and gloss were not adversely affected by the introduction of any of the tung oil based diluents. 相似文献
Two UV-curable tung oil-based resins were synthesized via a Diels–Alder cycloaddition. An UV-curable tung oil (UVTO) was prepared from bodied tung oil and trimethylolpropane trimethacrylate (TMPTMA). An inhibitor, phenothiazine, was added to avoid homopolymerization of TMPTMA. The UV-curable tung oil alkyd (UVTA) was prepared from the monoglyceride process and then reacted with TMPTMA via the Diels–Alder reaction similar to the UVTO. The UVTO and UVTA were characterized by 1H NMR, 13C NMR, and MALDI-TOF mass spectroscopy. The UVTO and UVTA were formulated with a free radical reactive diluent, tripropylene glycol diacrylate (TPGDA) and photoinitiator Irgacure 2100. Photo differential scanning calorimeter (Photo-DSC) was used to investigate curing kinetics of the UVTO and the UVTA. Both the UVTO and UVTA were photocurable with the UVTA formula exhibiting a faster curing speed than the UVTO. 相似文献
Sucrose octasoyate (SS8) was investigated as a reactive diluent for a medium oil alkyd (MOA). SS8, which is derived from sugar and soybean oil, is 100% biobased, nontoxic, and biodegradable. As a result of its unique molecular architecture, it was expected that SS8 would be an excellent reactive diluent for alkyd coatings. The experiment conducted basically involved the incremental replacement of the MOA with SS8, while maintaining essentially equivalent solution viscosity. The properties of cured coatings were determined using industry standard methods. In general, it was found that SS8 could be used to reduce volatile organic compound content of the coatings, while also reducing drying time (i.e., tack-free time), increasing solvent resistance, and increasing impact resistance. Of the properties measured, the only cured film property that was negatively affected by the use of SS8 was the König pendulum hardness. However, the reduction in König pendulum hardness was only observed when the amount of MOA replaced by SS8 was greater than 10 wt%. Overall, these initial results suggest that SS8 is a very good reactive diluent for alkyd coatings. 相似文献
Environmental regulations are forcing the reformulation of many decorative and protective coatings systems. In particular,
air-drying solventborne alkyd paints need to meet increasingly stringent emission limits and often must be reformulated with
suitable exempt solvents or reactive diluents to achieve volatile organic compound (VOC) reduction. In the research summarized
in this article, a new reactive diluent, tetra(2,7-octadienyl) titanate, was synthesized and evaluated in alkyd formulations
for VOC reduction and property enhancement. A soy-based long-oil alkyd resin; a soy-based high-solids, long-oil alkyd resin;
and a linseed-based, high-solids long-oil alkyd resin were evaluated in combination with the new reactive diluent at weight
percentages ranging from 10% to 50%. Characterization included measuring viscosity, film dry times, and film performance of
the reactive diluent formulations in comparison to neat alkyd resins used as control. The tetra(2,7-octadienyl) titanate formulations
consistently exhibited reduced viscosities and dry times as a function of concentration. The resulting films were harder and
more thoroughly cured than the control systems. 相似文献
The development of air-drying solvent borne trade paints with solvent content below that of current solids levels will necessitate reformulation using reactive diluents. The current lack of suitable reactive diluents for air-drying systems has prompted this investigation. This paper highlights some emerging aspects of the design of reactive diluents, in particular the importance of inclusion of the correct balance of sites for both initiation and coupling reaction stages into an alkyd system together with the concept of functionality as a tool to predict performance. Also reported is a new class of reactive diluents based on fumarates and succinates of octadienol (referred to as the OFS class of reactive diluents). A detailed study on the cure and performance of this class of compounds is reported. A combination of conventional and refined analytical techniques have given new insights into the mechanism of cure of these reactive diluents as well as a measurement of incorporation into the drying paint film. The findings of this performance study have confirmed the suitability of the reactive diluent design and allowed its further refinement. OFS reactive diluents have thus been found to achieve full chemical incorporation whilst maintaining high performance of the paint. 相似文献
The coating of a plastic substrate (polycarbonate sheets) with different uv-curable system was investigated. Systems based on an epoxy-acrylate resin (bisphenol-A-diglycidyl-ether-diacrylate) or on bisphenol-A-diethoxy-diacrylate were used in the presence of different reactive diluents. Pull-off experiments indicated that the presence of a reactive diluent able to dissolve or swell the polycarbonate matrix increased the adhesion properties; poor adhesion values were obtained by using reactive diluents which did not dissolve the polymer. When vinyl-pyrrolidone (VP) was used asa reactive diluent, Fourier transform infra-red analysis indicated that the VP diffused ino the polycarbonate matrix. Dynamic mechanical thermal analyses performed on thin films of polycarbonate attributable to the two polymeric phases. In the presence of diluent, the tan regions attributable to the two polymeric phases. In the presence of VP diluent, the tan σ peak of the coating phase was broader, thus suggesting the presence of a transition layer between the two phases. 相似文献
Three new reactive diluents were prepared from tung oil using a Diels‐Alder reaction. The dienophiles were methacryloxypropyl trimethoxysilane (MAS), 2,2,2‐trifluoroethyl methacrylate (TFM) and triallyl ether acrylate (TAEA). The chemical structures were evaluated using 1H NMR, 13C NMR, FT‐IR, GPC and MALDI‐TOF‐MS. Spectra evidence (NMR, MS) indicated that a six‐member ring were formed in all three reactions indicating a Diels‐Alder adduct. The reactive diluents were formulated with a soya‐based alkyd to evaluate viscosity reduction and drying time. The viscosity of alkyd was reduced up to 70% using the reactive diluents. The drying time for the autoxidative reactive diluents with alkyds were 1.8‐1‐7 times faster than alkyd alone.
A series of dual curable polyurethane methacrylate-based oligomers were synthesized by changing the NCO:OH ratio and then were included in adhesive formulations using trimethylolpropane trimethacrylate and tricyclodecane dimethanol diacrylate (TCDDA) as reactive diluents. The effects of NCO:OH ratio and reactive diluent type on the structural properties of UV-cured free films and adhesion properties between polyester cord/rubber surfaces were studied. The highest adhesion strength of the 103?N?cm?1 was obtained when the NCO:OH ratio was set as 4 and the TCDDA was used as a reactive diluent. 相似文献
A UV-curable acrylated urethane prepolymer was synthesized from tolylene-2,4-diisocyanate (TDI), a polyether polyol (Arcol 1131) and endcapped with 2-hydroxyethyl methacrylate (HEMA) by addition reaction in the presence of dibutyltin dilaurate as catalyst. UV curing was performed with either diethylene glycol diacrylate or thiodiethylene glycol diacrylate as reactive diluent. The effects of reactive diluent types, their concentrations and the humidity of environment on mechanical properties of cured films were investigated. Changes in the tensile strength, elongation and Young's modulus values of the cured films upon addition of reactive diluents with different concentrations were related to the effect of the diluent on the crosslinking density of cured films. The increase of relative humidity from 50 to 95% caused a decrease of tensile strength and Young's modulus values of cured films. It is proposed that the decrease of these physical properties in high relative humidity is due to the formation of hydrogen bonding in polymer chains caused by water molecules. 相似文献