Me hods
MBB p oduc ion
Fi e squa es (5 mm x 5 mm in dimensions) o mycelium g own on MEA we e shaken
(150 pm) wi h 200 ml 2%ME a 22°C o 13 days in o de o p epa e he liquid inoculum o G.
sessile. Liquid cul u es we e p epa ed by inocula ion o 200 ml 2%ME by 40 ml o inoculum,
and he cul u es we e cul i a ed a 20°C o 7 days by cons an shaking a 150 pm. A e 7
days, 5% (d y weigh / olume) o pul e ised nu shells we e added o he liquid cul u e and
shaken a he same condi ion o ano he 4 days. A e his pe iod, 40 g o he cul u e was
il e ed using a polye hylene (PE) il e wi h po es 29 μm in diame e , he p essu e du ing
il a ion was 20 mba . The il e cake was placed on a pe i dish and ligh ly co e ed in o de o
allow ai o en e he pe i dish and enable u he me abolic ac i i y o he mycelium. This
expe imen design enabled an addi ional 7-day-long solid-s a e e men a ion, a e which he
g owing composi e was u ned o e in o de o allow he mycelium o g ow p ope ly on bo h
sides. A e ano he 7 days, he composi es we e ully g own, and he g ow h was e mina ed
by acuum d ying a 70°C and 700 mba o 2 days. In o de o de e mine he d y mass o he
p oduced composi es, all samples we e o en-d ied a 103°C. This p ocedu e esul ed in he
p oduc ion o pa icle-based composi es bonded wi h mycelium non-wo en s uc u e; he
weigh pe uni a ea o he esul ing composi es om walnu shell pa icles was 1035 g/m2,
composi es om pis achio nu shells eached 935 g/m2 and e e ence wi hou nu shell pa icles
230 g/m2. The mycelium-based biocomposi es we e ea ed wi h glyce ol. Glyce ol ea men
was conduc ed as imme sion o he samples in 20% wa e solu ion o glyce ol o 96 hou s a
20°C. The lis o p oduced a ian s is p o ided in Table 1.
Table 1 Va ian s o mycelium-based biocomposi es
Va ian
Nu shell
T ea men
W0
Walnu
-
WG
Walnu
Glyce ol
P0
Pis achio
-
PG
Pis achio
Glyce ol
R0
-
-
RG
-
Glyce ol
Dynamic Vapou So p ion (DVS)
So p ion/deso p ion iso he ms we e de e mined using a DVS Ad an age appa a us (Su ace
Measu emen Sys ems L d., London, Uni ed Kingdom). All measu emen s we e conduc ed a
a cons an empe a u e o 25 °C. The measu emen p og am is illus a ed in Figu e 1. B ie ly,
he samples we e ini ially p e-d ied a 0% ela i e humidi y (RH) o 9 hou s. Following his, he
RH was inc eased in 20% inc emen s, each main ained o 3 hou s, un il eaching 100% RH.
The deso p ion cycle ollowed he same s eps in e e se, dec easing he RH in 20%
inc emen s om 100% back o 0%.
Figu e 1 The measu emen p og am o so p ion/deso p ion iso he ms de e mina ion
Dynamic Mechanical Analysis
Dynamic mechanical analysis (DMA) was conduc ed using DMA 303 Explexo (Ne zsch, Selb,
Ge many). The samples we e es ed using a p essu e mode, he equency was 1 Hz, he
dynamic de o ma ion was 0.03 mm, he dynamic o ce was 10 N, and he s a ic o ce was 13
N. The es ed empe a u e in e al was om 20°C o 230°C wi h an inc emen o 3°C/min. The
es ed MBB samples had dimensions o 5 mm × 5 mm × 1 mm (leng h × wid h × hickness). In
con as , he e e ence samples R0 and RG we e signi ican ly hinne , and i was no easible
o es a single laye o hese ma e ials. The e o e, hese samples o DMA we e p epa ed by
s acking i e laye s o R0 and RG o achie e compa able hickness. I should be no ed ha
his laye ed s uc u e di e s om he s uc u e o he MBB samples con aining nu shell
pa icles. This s uc u al di e ence mus be aken in o accoun when in e p e ing he DMA
esul s.
Sho e Ha dness
Sho e ha dness was measu ed using a Sho e du ome e (PTC Ins umen s, USA), in
acco dance wi h he EN ISO 868. Sho e A me hod wi h a la ened ip o he inden e was
employed. Al hough he Sho e A me hod is p ima ily in ended o es ing lexible ma e ials, i
was employed in his s udy because he p oduced composi es we e b i le, and al e na i e
ha dness es ing me hods led o ma e ial chipping. Each a ian was measu ed 10 imes.
Simul aneous The mal Analysis (STA)
The he mal decomposi ion beha iou o he ma e ial was analysed by simul aneous he mal
analysis (STA) using a Ne zsch STA 409 PG unde py oly ic condi ions wi h a ni ogen low o
60 mL/min. P io o measu emen , he sample was g ound o a pa icle size below 0.5 µm using
a Re sch Ul a Cen i ugal Mill ZM 200. The analysis was pe o med in wo s eps. In he i s
s ep, he sample was hea ed o 105 °C, ollowed by a 10-minu e iso he mal d ying phase.
A e wa d, he sample was cooled o 20 °C using liquid ni ogen. In he second s ep, he
ma e ial was hea ed o 600 °C a a hea ing a e o 10 K/min. An illus a ion o he measu emen
p og am can be ound in Figu e 2.
0
10
20
30
40
50
60
70
80
90
100
39
40
41
42
43
44
45
46
47
0 500 1000 1500 2000 2500
Ta ge RH (%)
Mass (mg)
Time (min)
Mass
Ta ge RH
Figu e 2 Measu emen p og am used in STA expe imen s
Fou ie -T ans o m In a ed Spec oscopy (FT-IR)
To conclude on di e ences in he chemical composi ion o he ilms, FT- IR spec a we e
acqui ed wi h 32 scans using an ATR-uni a ached o an FT-IR spec ome e (Ve ex 70,
B uke , Bille ica, USA). The d y samples we e milled o ha e a homogeneous mix u e and ou
spec a measu ed, a e aged and cu o he mos ele an wa enumbe ange om 1800 cm-1
o 850 cm-1 using OPUS 7.5 so wa e (B uke , USA).
