US 12,428,501 B2
Method for producing removable pressure-sensitive adhesives (PSAs) using bio-based starting materials
Adrian Badia, Leioa (ES); Jose Ramon Leiza, Leioa (ES); and Maria Jesus Barandiaran, Leioa (ES)
Assigned to The University of the Basque Country, (ES); and Basque Center For Macromolecular Design and Engineering, Polymat Fundazio, (ES)
Appl. No. 18/009,842
Filed by The University of the Basque Country, Leioa (ES); and Basque Center For Macromolecular Design and Engineering, Polymat Fundazioa, Donostia—San Sebastián (ES)
PCT Filed Aug. 25, 2020, PCT No. PCT/EP2020/073723
§ 371(c)(1), (2) Date Dec. 12, 2022,
PCT Pub. No. WO2021/249660, PCT Pub. Date Dec. 16, 2021.
Claims priority of application No. PCT/EP2020/066038 (WO), filed on Jun. 10, 2020.
Prior Publication US 2023/0227588 A1, Jul. 20, 2023
Int. Cl. C08F 2/24 (2006.01); C08F 265/06 (2006.01); C09J 7/38 (2018.01); C09J 133/10 (2006.01)
CPC C08F 2/24 (2013.01) [C08F 265/06 (2013.01); C09J 7/385 (2018.01); C09J 133/10 (2013.01); C09J 2301/302 (2020.08); C09J 2301/502 (2020.08)] 28 Claims
OG exemplary drawing
 
1. A method for producing a polymeric composition,
wherein the method comprises a two-stage emulsion polymerization process,
wherein:
(a) in a first stage (a), a copolymerization of monomers (i), (ii) and (iii) is performed via emulsion polymerization, wherein
(i) monomer (i) comprises at least one ethylenically unsaturated monomer, a homopolymer which has a glass transition temperature Tg(i) ranging from −100° C. to −10° C.,
(ii) monomer (ii) comprises at least one mono- or difunctional bicyclic monomer comprising at least one substituent comprising one ethylenically unsaturated bond wherein the at least one mono- or difunctional bicyclic monomer is derived from isosorbide or from (iso) borneol,
(iii) monomer (iii) comprises at least one ethylenically unsaturated carboxylic acid,
so as to produce a first copolymer (A) which comprises moieties (i), (ii) and (iii) each as defined hereinabove and contains free carboxylic groups —C(O)—OH, followed by a conversion of the free carboxylic groups into carboxylate groups —C(O)—O−,
wherein, in the first stage (a), the monomers (moieties) (i), (ii) and (iii) are used in a (i)/(ii)/(iii)-weight ratio of (30-93)/(2-25)/(5-45),
wherein the first stage (a) is performed until a weight-average molecular mass Mw of the first copolymer (A) in a range of from 2,000 to 50,000 Daltons has been reached, as determined by size exclusion chromatography in accordance with DIN EN ISO 16014-5:2019 and measured with a fraction soluble in tetrahydrofuran,
wherein the first stage (a) is performed such as to produce the first copolymer (A) which has an acid value AV as determined before the conversion of the free carboxylic groups into carboxylate groups in a range of from 75 to 140 mg KOH/g, as determined by titration in accordance with ASTM D664;
subsequently
(b) in a second stage (b), a copolymerization of monomers (i) and (ii) is performed via emulsion polymerization in the presence of the carboxylate groups containing first copolymer (A) obtained from stage (a),
wherein monomers (i) and (ii) correspond each to the above definitions, however, with the proviso that monomers (i) and (ii) used in the second stage (b) may be the same as or different from those used in the first stage (a),
so as to produce a graft copolymer (B) comprising a copolymeric structure of moieties (i) and (ii) obtained from the second stage (b) copolymerization and which is covalently bonded with the first copolymer (A) via grafting.