Potato starch packaging was the most rapidly degraded material by HC tested in this
investigation and 91 % of the input mass was destroyed after 67 days and complete
degradation occurred after 126 days. The decomposition of waxed cardboard materials also
occurred in home composters and varied from approximately 60 % degradation to almost
complete destruction. Thus, solid bleached cardboard (doughnut box) achieved the highest
degradation value (99 %) followed by waxed corrugated cardboard (Pizza box), which was
degraded by 77 %. Lower rates of degradation (58-59 %) were measured for heavily waxed
corrugated cardboard (laundry tablets box) and solid unbleached cardboard. Bleached white
line chipboard (disposable plate) was degraded by 41 % whereas white line chipboard
(breakfast cereal boxes) had lower rates of decomposition of 28 - 36 %. The degradation of
folding boxboard (cheese box), which is heavily waxed for moisture resistance, and nonpackaging
waste cardboard (typical backing board to a notepad) was also relatively limited
and equivalent to 37 and 38 % of the input mass. No degradation of PLA took place in
home compost bins. This may be explained because the temperature conditions in home
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compost (Table 5.1) are too low to support the decomposition of this material