TY - JOUR
T1 - Development of Fertilizer Coatings from Polyglyoxylate-Polyester Blends Responsive to Root-Driven pH Change
AU - Heuchan, Spencer M.
AU - Fan, Bo
AU - Kowalski, Jessica J.
AU - Gillies, Elizabeth R.
AU - Henry, Hugh A.L.
PY - 2019/11/20
Y1 - 2019/11/20
N2 - Many current controlled-release fertilizers (CRFs) are coated with nonbiodegradable polymers that can contribute to microplastic pollution. Here, coatings of self-immolative poly(ethyl glyoxylate) (PEtG) capped with a carbamate and blended with polycaprolactone (PCL) or poly(l-lactic acid) (PLA) were evaluated. They were designed to depolymerize and release fertilizers in the vicinity of plant roots, where the pH is lower than that in the surrounding environment. PEtG/PCL coatings exhibited significant temperature and pH effects, requiring 18 days at pH 5 and 30 °C, compared to 77 days at pH 7 and 22 °C, to reach 15% mass loss. Plant roots were also effective in triggering coating degradation. Spray-coating and melt-coating were explored, with the latter being more effective in providing pellets that retained urea prior to polymer degradation. Finally, PEtG/PCL-coated pellets promoted plant growth to a similar degree or better than currently available CRFs.
AB - Many current controlled-release fertilizers (CRFs) are coated with nonbiodegradable polymers that can contribute to microplastic pollution. Here, coatings of self-immolative poly(ethyl glyoxylate) (PEtG) capped with a carbamate and blended with polycaprolactone (PCL) or poly(l-lactic acid) (PLA) were evaluated. They were designed to depolymerize and release fertilizers in the vicinity of plant roots, where the pH is lower than that in the surrounding environment. PEtG/PCL coatings exhibited significant temperature and pH effects, requiring 18 days at pH 5 and 30 °C, compared to 77 days at pH 7 and 22 °C, to reach 15% mass loss. Plant roots were also effective in triggering coating degradation. Spray-coating and melt-coating were explored, with the latter being more effective in providing pellets that retained urea prior to polymer degradation. Finally, PEtG/PCL-coated pellets promoted plant growth to a similar degree or better than currently available CRFs.
KW - biodegradation
KW - controlled release fertilizer
KW - microplastic
KW - pH-responsive
KW - poly(ethyl glyoxylate)
KW - self-immolative polymer
UR - http://www.scopus.com/inward/record.url?scp=85074905078&partnerID=8YFLogxK
U2 - 10.1021/acs.jafc.9b04717
DO - 10.1021/acs.jafc.9b04717
M3 - Article
C2 - 31652059
AN - SCOPUS:85074905078
SN - 0021-8561
VL - 67
SP - 12720
EP - 12729
JO - Journal of Agricultural and Food Chemistry
JF - Journal of Agricultural and Food Chemistry
IS - 46
ER -
