Novel reworkable resins: thermo‐ and photo‐curable di(meth)acrylates

Abstract

The aim of the study reported in this paper was to develop new di(meth)acrylates having aromatic units and thermally degradable units in their molecules. It was also the aim to clarify the photo‐curing and degradation properties of the new monomers. Di(meth)acrylates having aromatic units and thermally degradable units were synthesized. As thermally cleavable linkages, tertiary ester moieties were incorporated into the di(meth)acrylates. Three types of processes for curing and degradation of the cured resins were studied: thermal curing and thermal degradation; thermal curing and photodegradation; and photo‐curing and thermal degradation. In the thermal curing and photodegradation process, di(meth)acrylate films containing a thermally induced radical initiator and a photoacid generator (PAG) became insoluble in solvents on heating. The cured films became soluble in solvents after ultraviolet irradiation followed by baking. The re‐dissolution behaviors were strongly affected by the structures of the PAGs. A mechanism for the photo‐ or thermo‐curing and photoassisted thermal degradation was studied using Fourier transform infrared, 1H NMR, thermogravimetric, mass spectrometric and size exclusion chromatographic analyses. Copyright © 2009 Society of Chemical Industry

Photo-degradation of Reworkable Resin: A Mechanical Study

“…Based on this point of view, we have developed a series of "reworkable" epoxy resins having tertiary ester linkages [5][6][7][8][9][10][11], sulfonate ester linkages [12], and hemiacetal ester linkages [13] as thermallycleavable units. The reactivity, sensitivity, thermal or chemical stability, and re-dissolution property of the polymers must be improved in terms of their practical use.…”

“…Reworkable resins [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15], which are thermosets thermally or chemically degradable under a given condition, have been extensively studied as environmentally-friendly materials without damaging the underlying materials. Based on this point of view, we have developed a series of "reworkable" epoxy resins having tertiary ester linkages [5][6][7][8][9][10][11], sulfonate ester linkages [12], and hemiacetal ester linkages [13] as thermallycleavable units.…”

Photocrosslinkable polymers with degradable properties

“…Multifunctional methacrylate monomers (8-11) bearing tertiary ester degradable units were also prepared. [18][19][20] Structures of these monomers are shown in Figure 3. UV curing of the monomers was performed via conventional radical polymerization, and complete insolubilization was observed.…”

“…As shown in Figure 5, the polymers (19)(20)(21)(22) containing both crosslinkable units, such as epoxies or oxetanes, and thermally degradable units, such as tertiary esters of carboxylic acid, sulfonic acid esters and carbonate esters, in their side chains were prepared. [28][29][30][31][32][33] Polymers 19-22 were synthesized using conventional radical copolymerization of the corresponding vinyl monomers.…”

Positive‐tone photoresist consisting of a multifunctional acrylate resin that can be patterned after photo‐crosslinking

“…To this aim, various materials with the ability to decompose via heat or light have been proposed . Multi‐functional (meth)acrylates with structures such as tertiary ester, acetal, and carbonate, which experience bond cleavage in acid, have been reported. The research group of Osaka Prefecture University has developed a radically curable tri‐functional methacrylate resin with a decomposition function .…”