Document 4JpnqkMEn0YgjrXrg4papDwmR
ACS Sustainable Chemistry & Engineering
Table 1. Estimated Half-Lives of Common Plastic Itemsa
Estimated Specific Surface Degradation Rate (min-max; m year-1)b
Estimated half-lives (min-max; year)
Plastics type
Common applications
Typical thickness (m)
Land (buried)
Land (accel. by UV/heat)c
Marine
Marine (accel. by UV/heat)c
Land Land (buried) (accel. by UV/heat)c
Marine
Marine (accel. by UV/heat)c
1. PET Single-use water
500
0
-
-
110
>2500d
-
-
2.3
bottle
2. HDPE Plastic bottles
500
1.0
1.3 (0.55-2.6) 4.3 (0-11)
9.5 (4.5-22)
250 (230-280) 190 (95-460)
58 (23 to >2500) 26 (12-55)
(0.91-1.1)
2. HDPE Pipes 3. PVC Pipes
10,000 10,000
1.0 (0.91-1.1)
0
1.3 (0.55-2.6) -
4.3 (0-11) -
9.5 (4.5-22) -
5000 (4600-5500)
>2500d
3900 (1900-9000) -
1200 (450 to >2500)
-
530 (230-1100) -
4. LDPE Plastic bags
100
11
22 (1.6-83)
15 (0-37)
10 (9.0-12)
4.6
2.3 (0.6-32)
3.4 (1.4 to >2500) 5 (4.2-5.5)
5. PP
Food storage
800
-
0.51
7.5
4.6
-
780
53
87
container
6. PS
Insulating packaging
20,000
0
-
-
-
>2500d
-
-
-
7. Others Biodegradable plastic
100
bag
270
320
(20-1400)
16
180
(7.5-29)
0.19
0.16
(0.035-2.5)
3.1 (1.7-6.7)
0.29
aHalf-life refers to conversion of the first 50% of the polymer mass, assuming pseudo-zeroth-order kinetics (i.e., invariant SA). According to eq 10, assuming cylindrical geometry and decreasing radius (but not height) over time predicts half-lives that are twice as long. Entries shown as (-) correspond to conditions for which no published data were found. Values in parentheses correspond to the range based on published reports. All values were rounded to two significant figures. bValues of 0 m year-1 correspond to reports in which no degradation was observed; however it is likely that the duration of the experiment was too short to measure an appreciable weight loss. These values were included in calculations of average degradation rates and in the corresponding time ranges for complete degradation. cCorresponds to data collected in the presence of a degradation accelerant (e.g., UV pretreatment, thermal pretreatment, or microbial incubation) and/or for plastics containing a rapidly degrading filler (e.g., starch, PLA, etc.). d>2500 indicates that the relevant studies detected no measurable degradation, possibly due to the duration of the experiment being too short, allowing only an estimated lower limit for the extrapolated degradation time. The value 2500 years was obtained by calculating a SSDR based on the sensitivity of the balance used in the study and extrapolating a half-life for the thinnest material (100 m, ca. 2500 years).
3502
pubs.acs.org/journal/ascecg
https://dx.doi.org/10.1021/acssuschemeng.9b06635 ACS Sustainable Chem. Eng. 2020, 8, 3494-3511
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