Formulation parameters influencing self-stratification of coatings

Self-stratified bio-based coatings: Formulation and elucidation of critical parameters governing stratification

“…Once the solvents are evaporated, the mobility of the resins is no longer ensured and the system then crosslinks, leading to a non-stratified coating. Finally, similarly to the conclusions of Vink [22], the stratification process occurs if the solvent evaporation rate is neither too high (because the binders need enough time to separate in a low-viscosity medium) nor too low (to induce the resins displacement and to avoid the cross-linking reaction to be complete before the total evaporation of the solvents) for epoxy resins with high affinity with the solvent blend. Solvent evaporation rate is thus a critical parameter for self-stratification to occur.…”

“…To conclude, a high solvent evaporation rate seems to be preferable for the stratification process to occur but it should not be too high because the binders need enough time to separate in a low-viscosity medium [22]. Indeed, other experiments were carried out with GE60 resin (more compatible with the solvent blends according to Hansen Solubility Parameters) and showed that with the most volatile solvent blend (BuAc/MIBK), no stratification was observed.…”

“…Indeed, Funke was the first to demonstrate that in the case of self-stratifying powder coatings, surface energy difference between two resins is the primary driving force for stratification [20] and this has been confirmed by numerous authors [22][27]. More precisely, Vink et al who studied a range of parameters which can influence the stratification process (curing agent, particle size, solvent evaporation, solubility …) finally concluded that the surface tension of the resins has a decisive role in the formation of two distinct layers [22]. Additionally, in 2009, Kuczynska et al demonstrated that, in their epoxy/acrylic formulations, the surface energy and in particular the polarity of acrylic resins are the most critical parameters for self-stratification to occur [28].…”

“…Binary resins system orientation may be driven by their difference in surface energy, which can also be responsible for the system stability [20]. Indeed, Funke was the first to demonstrate that in the case of self-stratifying powder coatings, surface energy difference between two resins is the primary driving force for stratification [20] and this has been confirmed by numerous authors [22][27]. More precisely, Vink et al who studied a range of parameters which can influence the stratification process (curing agent, particle size, solvent evaporation, solubility …) finally concluded that the surface tension of the resins has a decisive role in the formation of two distinct layers [22].…”

“…In the literature, influence of some parameters of different systems are thus discussed [22] but the conclusions are sometimes contradictory according to the authors. As far as we know, no recent paper deals with a systematic approach of formulation and elucidation of critical parameters governing stratification.…”

Self-stratified bio-based coatings: Formulation and elucidation of critical parameters governing stratification

“…Once the solvents are evaporated, the mobility of the resins is no longer ensured and the system then crosslinks, leading to a non-stratified coating. Finally, similarly to the conclusions of Vink [22], the stratification process occurs if the solvent evaporation rate is neither too high (because the binders need enough time to separate in a low-viscosity medium) nor too low (to induce the resins displacement and to avoid the cross-linking reaction to be complete before the total evaporation of the solvents) for epoxy resins with high affinity with the solvent blend. Solvent evaporation rate is thus a critical parameter for self-stratification to occur.…”

“…To conclude, a high solvent evaporation rate seems to be preferable for the stratification process to occur but it should not be too high because the binders need enough time to separate in a low-viscosity medium [22]. Indeed, other experiments were carried out with GE60 resin (more compatible with the solvent blends according to Hansen Solubility Parameters) and showed that with the most volatile solvent blend (BuAc/MIBK), no stratification was observed.…”

“…Indeed, Funke was the first to demonstrate that in the case of self-stratifying powder coatings, surface energy difference between two resins is the primary driving force for stratification [20] and this has been confirmed by numerous authors [22][27]. More precisely, Vink et al who studied a range of parameters which can influence the stratification process (curing agent, particle size, solvent evaporation, solubility …) finally concluded that the surface tension of the resins has a decisive role in the formation of two distinct layers [22]. Additionally, in 2009, Kuczynska et al demonstrated that, in their epoxy/acrylic formulations, the surface energy and in particular the polarity of acrylic resins are the most critical parameters for self-stratification to occur [28].…”

“…Binary resins system orientation may be driven by their difference in surface energy, which can also be responsible for the system stability [20]. Indeed, Funke was the first to demonstrate that in the case of self-stratifying powder coatings, surface energy difference between two resins is the primary driving force for stratification [20] and this has been confirmed by numerous authors [22][27]. More precisely, Vink et al who studied a range of parameters which can influence the stratification process (curing agent, particle size, solvent evaporation, solubility …) finally concluded that the surface tension of the resins has a decisive role in the formation of two distinct layers [22].…”

“…In the literature, influence of some parameters of different systems are thus discussed [22] but the conclusions are sometimes contradictory according to the authors. As far as we know, no recent paper deals with a systematic approach of formulation and elucidation of critical parameters governing stratification.…”

Self-stratified bio-based coatings: Formulation and elucidation of critical parameters governing stratification

“…Once the solvents are evaporated, the mobility of the resins is no longer ensured and the system then crosslinks, leading to a non-stratified coating. Finally, similarly to the conclusions of Vink [22], the stratification process occurs if the solvent evaporation rate is neither too high (because the binders need enough time to separate in a low-viscosity medium) nor too low (to induce the resins displacement and to avoid the cross-linking reaction to be complete before the total evaporation of the solvents) for epoxy resins with high affinity with the solvent blend. Solvent evaporation rate is thus a critical parameter for self-stratification to occur.…”

“…To conclude, a high solvent evaporation rate seems to be preferable for the stratification process to occur but it should not be too high because the binders need enough time to separate in a low-viscosity medium [22]. Indeed, other experiments were carried out with GE60 resin (more compatible with the solvent blends according to Hansen Solubility Parameters) and showed that with the most volatile solvent blend (BuAc/MIBK), no stratification was observed.…”

“…Indeed, Funke was the first to demonstrate that in the case of self-stratifying powder coatings, surface energy difference between two resins is the primary driving force for stratification [20] and this has been confirmed by numerous authors [22][27]. More precisely, Vink et al who studied a range of parameters which can influence the stratification process (curing agent, particle size, solvent evaporation, solubility …) finally concluded that the surface tension of the resins has a decisive role in the formation of two distinct layers [22]. Additionally, in 2009, Kuczynska et al demonstrated that, in their epoxy/acrylic formulations, the surface energy and in particular the polarity of acrylic resins are the most critical parameters for self-stratification to occur [28].…”

“…Binary resins system orientation may be driven by their difference in surface energy, which can also be responsible for the system stability [20]. Indeed, Funke was the first to demonstrate that in the case of self-stratifying powder coatings, surface energy difference between two resins is the primary driving force for stratification [20] and this has been confirmed by numerous authors [22][27]. More precisely, Vink et al who studied a range of parameters which can influence the stratification process (curing agent, particle size, solvent evaporation, solubility …) finally concluded that the surface tension of the resins has a decisive role in the formation of two distinct layers [22].…”

“…In the literature, influence of some parameters of different systems are thus discussed [22] but the conclusions are sometimes contradictory according to the authors. As far as we know, no recent paper deals with a systematic approach of formulation and elucidation of critical parameters governing stratification.…”

Self-stratified bio-based coatings: Formulation and elucidation of critical parameters governing stratification

“…Once the solvents are evaporated, the mobility of the resins is no longer ensured and the system then crosslinks, leading to a non-stratified coating. Finally, similarly to the conclusions of Vink [22], the stratification process occurs if the solvent evaporation rate is neither too high (because the binders need enough time to separate in a low-viscosity medium) nor too low (to induce the resins displacement and to avoid the cross-linking reaction to be complete before the total evaporation of the solvents) for epoxy resins with high affinity with the solvent blend. Solvent evaporation rate is thus a critical parameter for self-stratification to occur.…”

“…To conclude, a high solvent evaporation rate seems to be preferable for the stratification process to occur but it should not be too high because the binders need enough time to separate in a low-viscosity medium [22]. Indeed, other experiments were carried out with GE60 resin (more compatible with the solvent blends according to Hansen Solubility Parameters) and showed that with the most volatile solvent blend (BuAc/MIBK), no stratification was observed.…”

“…Indeed, Funke was the first to demonstrate that in the case of self-stratifying powder coatings, surface energy difference between two resins is the primary driving force for stratification [20] and this has been confirmed by numerous authors [22][27]. More precisely, Vink et al who studied a range of parameters which can influence the stratification process (curing agent, particle size, solvent evaporation, solubility …) finally concluded that the surface tension of the resins has a decisive role in the formation of two distinct layers [22]. Additionally, in 2009, Kuczynska et al demonstrated that, in their epoxy/acrylic formulations, the surface energy and in particular the polarity of acrylic resins are the most critical parameters for self-stratification to occur [28].…”

“…Binary resins system orientation may be driven by their difference in surface energy, which can also be responsible for the system stability [20]. Indeed, Funke was the first to demonstrate that in the case of self-stratifying powder coatings, surface energy difference between two resins is the primary driving force for stratification [20] and this has been confirmed by numerous authors [22][27]. More precisely, Vink et al who studied a range of parameters which can influence the stratification process (curing agent, particle size, solvent evaporation, solubility …) finally concluded that the surface tension of the resins has a decisive role in the formation of two distinct layers [22].…”

“…In the literature, influence of some parameters of different systems are thus discussed [22] but the conclusions are sometimes contradictory according to the authors. As far as we know, no recent paper deals with a systematic approach of formulation and elucidation of critical parameters governing stratification.…”