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Abstract

In this study, wood-plastic composites (WPC) were produced by rotomoulding, to study the effect of fibre content and surface treatment on their properties. Maple wood fibre, with or without surface treatment with maleated polyethylene (MAPE), was used to improve the mechanical properties of linear low-density polyethylene (LLDPE). From the composites produced, a complete morphological and mechanical characterisation was performed. The results showed that MAPE surface treatment improved the fibre-matrix interface quality and the mechanical properties (56% increase in tensile modulus and 60% increase in flexural modulus over the neat matrix with 19% in impact strength with respect to untreated fibres) at 30% wt.

Keywords

LLDPE maple MAPE solution modification rotomoulding mechanical properties

1. Introduction

Rotational moulding, also known as rotomoulding or rotocasting, is a manufacturing process having virtually unlimited design possibility to produce complex shapes over a wide range of sizes. But the main advantage of rotomoulding is the possibility to produce hollow parts without weld-lines which are always weak points, especially for polymer composites. Compared to other plastic moulding processes like injection moulding, rotational moulding benefits from low-cost moulds (material and thickness) since no pressure is applied on the materials leading to stress-free parts. The thickness of the final part is directly related to the amount of material loaded, as well as the biaxial rotational speed and mould thickness. Nevertheless, rotational moulding also has some disadvantages, the main ones being long cycle times and the limited range of materials to select from^1–3.

The rotational moulding cycle can be decomposed into four stages. Firstly, the mould is charged with a predetermined amount of materials (powders, micro-pellets or viscous liquids). Then, the mould is closed, starts to rotate about two perpendicular axes where the velocity in each direction (speed ratio) is carefully controlled, and placed inside a heated oven. Once the material has fully melted and sintered (heating step), the mould is moved to a cooling stage using air (forced convection), water mist or a combination of both. When the material can be handled, the product is demoulded and a new cycle begins⁴.

Nowadays, the main rotational moulding applications are automotive (ducting, fuel tanks, etc.), marine industry (kayaks, dock floats, etc.), containers (tanks, reservoirs), and general industrial products (tool boxes, containers, toys, etc.)⁴. Polyvinyl chloride (PVC) was the first polymer introduced for different articles like toys and car interiors (door panels, dash-boards). In the late 1950s, polyethylene powder became available for rotational moulding applications. Today, the different grades of polyethylene (LLDPE, LMDPE, LDPE, HDPE, MDPE, etc.) represent close to 90% of all the polymers rotationally moulded^4–6. Recently, there has been increasing interest in the rotational moulding of composite parts to reduce costs (using low cost fillers) and/or improve mechanical properties. Over the last years, the average sales of the North American rotomoulding business sustained an annual growth rate of 7.2% between 2009 and 2014⁷. A similar trend was observed for composite materials as the total sales of the North American production was about $7.4 billion in 2013 and is expected to increase to $11.3 billion by 2019⁸. For these materials, their main applications are in transportation, civil infrastructure, sporting goods, packaging, as well as different commercial and engineering applications⁸. One reason for the growing commercial production of polymer composites is the interest being given to natural fibres (lignocellulosic) because they are ecologically and toxicologically harmless, biodegradable, CO₂ neutral, low cost and lightweight^9–11.

To rotomould a composite part based on a thermoplastic matrix and a reinforcing particle, two techniques can be used. The first method is to produce a compound via melt blending (batch mixer, twin-screw extrusion, etc.), then to pelletise/pulverise the materials. Good adhesion (especially if coupling agents are added) and dispersion of the solid particles is expected by this technique, but thermo-oxidative and mechanical degradation of the materials (matrix and reinforcement) is expected in every processing step. To overcome some of these problems, a second methodology was developed more recently: dry-blending. As all the initial materials are in a powder form, high-shear mixers can be used to disperse the materials before being loaded in the mould. This method has several benefits as being fast, low cost and very limited material degradation occurs¹². Nevertheless, this method has some limitations, the main one being the poor adhesion (interfacial voids) at the particle-matrix interface due to the lack of compatibility and the absence of pressure to compact the materials. This led to low mechanical properties of the final product. Fortunately, this problem can be solved by performing a surface treatment on the particles as the interface between the fibres and the matrix is controlling the mechanical properties of composites. Poor adhesion results in low interfacial interaction limiting load transfer and leading to composites having low mechanical properties¹³. But the polar and hydrophilic natural fibres are incompatible with most polymers which are non-polar and hydrophobic. This incompatibility leads to poor interface quality and poor mechanical performances^10–14. But good interfacial adhesion (compatibility) between natural fibres and polymer matrices can be achieved by using physical or chemical surface treatments^13–15. This can also lead to other advantages like improved mechanical properties, moisture resistance and better fibres distribution allowing the possibility to use higher fibre contents in rotational moulding^9–16. To this purpose, maleated copolymers (coupling agents) were developed as these molecules provide efficient interaction with the functional surface of the fibres and the matrix. A similar study was done by Gupta et al.¹⁷ and their results showed a significant modulus improvement which was attributed to polymer chains orientation during the biaxial orientation process. On the other hand, the elongation at break and fracture (break) stress decreased with up to 10% vol. of phosphate glass (P glass) in the composites as compared to neat poly(propylene-graft-maleic anhydride) (PPgMA). They also reported compatibility improvement as a result of maleated polypropylene being used as a reactive compatibiliser for polypropylene/inorganic glass composites. Gupta et al.¹⁸ studied the structure and gas barrier properties of PPgMA/P glass composites prepared by microlayer co-extrusion. They reported that better interfacial compatibility was the result of hydrogen bonding between the hydroxyl groups on the glass surface and the maleic anhydride group in PPgMA. This effect led to improved interfacial adhesion with well dispersed fillers when PPgMA was used as the polymer matrix¹⁸. Another example is maleated polyethylene (MAPE) where the maleic anhydride groups of MAPE can react with the hydroxyl groups (OH) of the amorphous region of cellulose, while physical entanglement can be obtained between the polyethylene molecules of the matrix and the PE part of MAPE. These interaction/reaction mechanisms were described in details elsewhere^19,20. Unfortunately, when a coupling agent is directly mixed with a polymer/fibre compound via melt blending, dispersion is not always guaranteed; so the best method to avoid this limitation, especially when using dry-blending, is to perform the fibre surface modification before their introduction in the matrix. This method can be done in solution and was successfully performed on maple and hemp by Cisneros-López et al.¹⁶, Chimeni et al.¹⁹, Verdaguer and Rodrigue²¹, and Raymond and Rodrigue²².

Based on the recent developments in rotomoulded composites, fibre surface treatment and dry-blending processing, the main objective of this work is to study the effect of fibre surface treatment (MAPE in solution) and concentration (10, 20 and 30%) on the morphological and mechanical properties of maple wood fibre/polyethylene composites.

2. Experimental

2.1. Materials

The polymer used was linear low-density polyethylene (LLDPE) powder (EXXON MOBIL LL 8555). The density of LLDPE is 936 kg/m³ with a melting temperature and melt flow index (MFI) of 126°C and 6.8 g/10 min (190°C/2.16 kg), respectively. The solvent used for wood fibre surface treatment was xylene (laboratory purity grade) from Fisher Chemicals (USA) and the coupling agent was maleic anhydride grafted polyethylene (MAPE): Epolene C26 (Westlake Chemicals, USA). The latter has an average molecular mass of 65 kg/mol, a MFI of 8.0 g/10 min (190°C/2.16 kg), an acid number of 8.0 mg KOH/g and a melting point of 121°C. As reinforcement, maple wood fibre was purchased from PWI Industries (Canada). The particles were sieved to keep only particles between 355 and 500 μm. This represents about the same range as the LLDPE powder to improve dry-blending and limit particle segregation.

2.2. Wood surface treatment

Wood surface treatment was performed as reported by Verdaguer and Rodrigue²¹. A solution of 1% MAPE in xylene was prepared at 80–90°C. Then, the wood particles were added and left for 30 min in the solution under high intensity mixing. A solid:solution (maple:xylene) ratio of 1:10 (w/v) was used²². Finally the treated wood particles were filtered and dried overnight at 60°C in an oven.

2.3. Sample production

The samples were produced using the following steps. Firstly, maple and LLDPE were dry-blended with a high shear mixer Skyfood LAR-15LMB (Skyfood, USA) at 3320 rpm for 4–5 min to get a homogeneous blend. Then, around 700 g of the powder blend was placed in an aluminium mould having a cubic shape (20 × 20 × 20 cm³) which was used to produce the rotationally moulded parts with an approximate wall thickness of 9.5 mm (3/8”) for the lateral and 12.7 mm (1/2”) for the top/bottom sides. Before loading, a demoulding agent (Trasys 420) was applied inside the mould. The charged mould was then closed and introduced into the oven which was previously heated at 280°C. Subsequently the mould was kept rotating for 20 min at a rotational speed ratio of 4:1, followed by a cooling period of 38 min with forced air (blowing fan).

2.4. Characterisations

2.4.1. Fourier transform infrared spectroscopy (FTIR)

Infrared spectra were obtained with a Nicolet FTIR spectrometer model 730 (Nicolet Instruments, USA) equipped with a mercury-cadmium-telluride detector. The absorbance was measured in the 4000–750 cm⁻¹ region. Each spectrum was obtained from 128 scans at a resolution of 4 cm⁻¹.

2.4.2. Thermogravimetric analysis (TGA)

The maple fibres (untreated and treated) were subjected to thermogravimetric analysis using a Q5000IR (TA Instruments, USA). Samples between 5 and 10 mg were analysed by heating up at 10°C/min from 50 to 700°C in a nitrogen atmosphere.

2.4.3. Morphology

For the morphological characterisation, a scanning electron microscope (SEM) JEOL JSM-840 was used. The moulded samples were first frozen in liquid nitrogen and then broken to be coated with Pd/Au prior to observation and images were taken at different magnifications.

2.4.4. Density

Density was obtained by a gas pycnometer ULTRAPYC 1200e (Quantachrome Instruments, USA) using nitrogen as the gas phase. The data reported are the average of five measurements while standard deviations were less than 1%.

2.4.5. Tension test

Young's modulus, tensile strength and elongation at break were measured using an Instron model 5565 universal testing machine (Instron, USA) with a 500 N load cell. Type V dog bones were cut from the moulded parts according to ASTM D638. The crosshead speed was set at 10 mm/min and the tests were performed at room temperature. Five samples were tested to report on the average and standard deviation.

2.4.6. Flexion test

Flexural tests were performed at room temperature using a crosshead speed of 2 mm/min on an Instron universal tester model 5565 (Instron, USA) with a 50 N load cell according to ASTM D790. Sample dimensions were 125 × 12.7 × 3 mm³ and the span length was fixed at 60 mm. At least five samples were used to report the average and standard deviation.

2.4.7. Impact test

Charpy impact strength test was done on a Tinius Olsen testing machine model Impact 104 (Tinius Olsen, USA) operating with a pendulum weight of 0.242 kg (1.22 J). The arm length was 279 mm, leading to an impact speed of 3.3 ms⁻¹. Rectangular samples with “V” notch produced by an automatic sample notcher model ASN (Dynisco, USA), at least 24 h before testing, were performed at room temperature and the results are the average of ten repetitions. For all the samples produced, Table 1 presents the list of codes used.

Table 1
Codes used for the samples produced

Code Samples names

LLDPE Linear low density polyethylene

UF LLDPE + Untreated maple

TF LLDPE + 1% MAPE solution modified maple

Code	Samples names
LLDPE	Linear low density polyethylene
UF	LLDPE + Untreated maple
TF	LLDPE + 1% MAPE solution modified maple

3. Results and Discussion

3.1. Confirmation of maple surface modification

FTIR, TGA, density and SEM tests were used to determine the level of surface modification on the maple fibres after solution treatment.

3.1.1. Fourier transform infrared (FTIR) spectroscopic analysis

The FTIR spectra of MAPE, untreated and treated maple fibres are shown in Figure 1 . MAPE shows strong peaks at 2923 and 2830 cm⁻¹ and 1751 cm⁻¹, belonging to symmetric and asymmetric aliphatic C–H vibration and C=O which are characteristic of the PE backbone and its ester group, respectively. The modified maple fibres showed an increase of the peaks at 2923 and 2830 cm⁻¹ and a weak one at 1011 cm⁻¹ suggesting an increase of C–H and C-C group in the modified fibres as they are characteristics of the alkane groups of MAPE. This observation shows that the MAPE was successfully grafted on maple fibres. This was also reported on maple fibres by Verdaguer and Rodrigue²¹, Raymond and Rodrigue²² and most recently on hemp fibres by Chimeni et al.¹⁹. The latter reported a mechanism involving the formation of additional hydroxyl groups on the fibres’ surface as a result of proton transfer after the reaction between the active sites on the fibres (OH) and the carbonyl groups of MAPE. To further confirm this result, thermogravimetric analysis of the neat and solution modified fibres was done.

Figure 1

FTIR spectra for MAPE, UF and TF maple fibres

3.1.2. TGA

Thermogravimetry was used to determine if MAPE was present on the fibre's surface. The corresponding TGA and DTG curves of untreated (UF) and MAPE solution treated (TF) maple fibres, as well as MAPE are presented in Figure 2 (a & b), respectively. The TGA ( Figure 2a ) curve of modified maple fibres is above the untreated curve over the entire range of temperature investigated. This is an indication that TF are more thermally stable than UF. This can be explained by the presence of a thin layer of MAPE on the surface of the fibres. This layer acted as a barrier enhancing the overall thermal stability of the fibres as MAPE is more stable than maple. This is confirmed by the DTG results presented in Figure 2b . The curve exhibits an initial weight loss around 70°C which is associated with water evaporation^21,22. But more importantly, the treated maple DTG curve presents an additional peak at 448°C corresponding to the thermal degradation of MAPE. Similar results have been reported for maple fibres by Verdaguer and Rodrigue²¹, Raymond and Rodrigue²², as well as hemp fibres by Chimeni et al.¹⁹ and agave fibres by Cisneros-López et al.¹⁶. To determine the amount of MAPE grafted onto the fibre's surface, the procedure established by Chimeni et al.²³ was used. According to this method, the loss weight peak (Δm) of MAPE (between 400°C and 500°C), can be determined according to:

m_{M A P E} = Δ m_{T F} - Δ m_{U F}

(1)

with Δm = m₂-m₁ where m₁ and m₂ are the mass of maple (solution treated or not) at 400°C and 500°C, respectively ( Figure 2 ). Then, the amount of MAPE grafted (T_GR) is determined as:

T_{G R} = m_{M A P E} * 100 / m_{1}

(2)

Figure 2

Thermogravimetric results: (a) TGA and (b) DTG curves

Using the experimental values, T_GR = 22%.

3.1.3. Density

To get more information about maple surface modification by MAPE in solution, the density of the fibres was measured and the results are presented in Table 2 . It is clear that the density of the treated fibres increased by about 10% compared to UT This can be associated with some lignins and hemicelluloses being extracted during the solution treatment at high temperature, as well as the effect of the MAPE layer coating the fibres thus increasing the fibre's weight and reducing porosity; i.e. the voids being filled with MAPE. To confirm this result, images of the particles before and after treatment were taken, as presented next.

Table 2
Density of the different raw materials used

Samples UF TF MAPE

Density (kg m⁻³) 1437 (7) 1590 (5) 988 (1)

Samples	UF	TF	MAPE
Density (kg m⁻³)	1437 (7)	1590 (5)	988 (1)

3.1.4. SEM of maple fibres

Figure 3a shows that the surface of neat maple fibres is very rough, with some parts being covered with impurities. On the other hand, the treated maple fibres have a more uniform surface texture due to the MAPE surface layer. This can be associated with the maleic anhydride groups of MAPE reacting with the hydroxyl groups (OH) of maple fibres²⁰, thus creating strong bonds between the two materials.

Figure 3

SEM images of: (a) untreated and (b) treated maple fibres

So, based on the characterisations made, it can be concluded that MAPE was successfully grafted onto the surface of the maple fibres.

3.2. Composite morphology

Figure 4 reveals that the composites based on neat maple (UF) have a high amount of holes. But these holes can be classified in two categories: holes produced by fibre debonding (white circles) and bubbles/voids (white squares). The debonding holes result from fibre pull-out and are typical in composites with poor fibre wettability and adhesion. On the other hand, bubbles/ voids are related to trapped air imprisoned between the powder particles due to incomplete sintering and/ or gases released by the fibres themselves (humidity and/or extractives). Figure 4 also shows that a more homogeneous morphology is obtained with less gaps and voids (white circles). This comes from better fibre dispersion/compatibility/wettability/adhesion due to the presence of a MAPE layer on the fibre surface.

Figure 4

Typical SEM images of untreated (a: 10%, c: 20% and e: 30%) and treated (b: 10%, d: 20% and f: 30%) maple fibre composites

3.2.1. Composite density

Table 3 reports on the density of LLDPE with and without solution-modified maple fibres. The results show that density increases with TF content as the density of TF ( Table 2 ) is higher than LLDPE (931 kg m⁻³). On the other hand, UF composites have lower densities than TF ones due to the presence of voids/gaps as seen in Figure 4 . Similar results were reported by Kakroodi et al.²⁵ showing that the addition of a coupling agent increases the composite density due to better interfacial contact between the fibres and the matrix.

Table 3
LLDPE density as a function of TF and UF content

Samples Fibre content (%) Density (kg m⁻³)

LLDPE 0 931 (7)

UF composites 10 961 (1)

20 989 (1)

30 1062 (1)

TF composites 10 996 (2)

20 1042 (2)

30 1079 (2)

Samples	Fibre content (%)	Density (kg m⁻³)
LLDPE	0	931 (7)
UF composites	10	961 (1)
20	989 (1)
30	1062 (1)
TF composites	10	996 (2)
20	1042 (2)
30	1079 (2)

3.3. Mechanical properties of the composites

3.3.1. Tensile properties

Figure 5 shows that the tensile modulus increased significantly for both UF and TF when compared to the neat matrix. This is due to the presence of the rigid wood particles^26,27. But in all cases, the composites prepared with TF have significantly higher values compared to UF composites: about 20, 12 and 11% respectively at 10, 20 and 30% maple. As reported by Raj and Kotka²⁶, the main factors affecting tensile modulus are: fibre aspect ratio, interfacial adhesion, and fibre concentration. As all the composites have the same fibre sizes, the increase must be related to the surface treatment for a fixed fibre content. Overall, the best improvement was obtained for 30% TF (272 MPa) with a 56% increase over neat LLDPE (174 MPa).

Figure 5

Tensile modulus as a function of UF and TF content

Figure 6 reports on the tensile strength of the samples presented in Figure 5 . It is clear that for UF composites, the values decrease linearly with maple content (about 28, 40 and 68% drop for 10, 20 and 30% fibre). A similar trend was observed by Ward-Perron et al.²⁸ and Jayaraman et al.²⁹. This behaviour is related to poor fibre-matrix adhesion limiting interfacial stress transfer^28,30. On the other hand, the tensile strength of TF composites is close to or slightly above the neat LLDPE value (15.5 MPa). These results can be associated to the MAPE layer on the fibre's surface acting as a coupling agent (see Figure 3 ) leading to better fibre contact with the matrix (see Figure 4 ). As a result of improved compatibility and adhesion, better interfacial stress transfer was obtained³¹. Nevertheless, the lower value at 30% maple (15.0 MPa) can be attributed to some agglomeration and/or particle-particle contact creating some defects in the composite structure. Nevertheless, the values is much higher than for UF (7.0 MPa).

Figure 6

Tensile strength as a function of UF and TF content

Figure 7 shows the elongation at break of the samples produced. It can be seen that the values are decreasing with fibre content and surface treatment do not significantly change this trend. Similar behaviour was also observed by Chimeni et al.¹⁹, Verdaguer and Rodrigue²¹, as well as Raymond and Rodrigue²² after using the same type of modification on hemp and maple fibres. As reported by Ndiaye and Tidjani³², lower elongation at break is related to the low elasticity of maple fibres and most composites based on rigid reinforcement have lower deformation (higher stiffness).

Figure 7

Tensile elongation at break as a function of UF and TF content

3.3.2. Flexural properties

Figure 8 compares the flexural modulus of UF and TF composites with neat LLDPE. For UF composites, the highest flexural modulus (877 MPa) is obtained at 30% wt. with a 42% increase compared with neat LLDPE (617 MPa). This significant increase is associated with the presence of rigid particles in the polymer matrix increasing the overall stiffness of the composite because maple fibres have a higher modulus (10–13 GPa) than the matrix^16,33. This is especially true for the top part of the sample, being in compression. On the other hand, higher flexural moduli were obtained by using TF and a 60% increase is obtained at 30% wt. This higher increase can be attributed to good interfacial bonding between the fibres and the matrix making more efficient all the reinforcement; i.e. the top part in compression and the bottom part in tension³³.

Figure 8

Flexural modulus as a function of UF and TF content

3.3.3. Impact properties

The Charpy impact strength results are presented in Figure 9 . As for the tensile elongation at break, the values are decreasing with fibre loading. But in this case, higher values are obtained with TF. Lower impact strength with increasing fibre content is expected, as the addition of rigid particles leads to more fibre-fibre interaction and fibre ends promoting defects and facilitating crack initiation and propagation^32–35. Since the interface is controlling the mechanical behaviour of composites, this is why the TF composites perform slightly better than UF, since a better interface was produced between maple fibres and LLDPE; i.e. lower amount of voids and defects. Nevertheless, more interfacial area is created with increasing fibre content and the addition of rigid particles both lead to lower impact strength, but the difference between UF and TF increases with fibre content (about 19% at 30% maple).

Figure 9

Charpy impact strength as a function of UF and TF content

4. Conclusion

This work investigated the effect of fibre surface modification (MAPE in solution) and fibre content (0–30% wt.) on the morphological and mechanical properties of maple/LLDPE composites produced by rotational moulding. From the samples produced, several conclusions can be made:

FTIR, SEM, density and TGA results showed that the surface modification in solution was successful and a thin MAPE (coupling agent) layer on the fibre surface was obtained. It is estimated that about 22% MAPE was grafted.

The morphological analysis of the composites showed that more homogeneous samples were produced with treated fibres, due to better interfacial contact and less defects compared to untreated maple. This led to higher composite density.

Finally, the mechanical properties (tensile modulus, tensile strength, flexural modulus and impact strength) of the composites based on treated maple fibres were all significantly improved. For example, tensile modulus (56%) and strength (10%) were increased at 30% and 20%, respectively for TF. On the other hand, elongation at break always decreased with both UF and TF.

Nevertheless, more work needs to be done to determine the optimum fibre content for a specific application.

Footnotes

Acknowledgement

The authors would like to thank the financial support of the Natural Sciences and Engineering Research Council of Canada (NSERC), the Research Center for high performance polymer and composite systems (CREPEC), as well as Centre de Recherches sur les Matέriaux Avancέs (CERMA) and Centre de Recherche sur les Matέriaux Renouvelables (CRMR) of Universitέ Laval for financial and technical support. The technical help of Mr. Yann Giroux was also much appreciated.

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Morphology and Mechanical Properties of Maple Reinforced LLDPE Produced by Rotational Moulding: Effect of Fibre Content and Surface Treatment

Abstract

Keywords

1. Introduction

2. Experimental

2.1. Materials

2.2. Wood surface treatment

2.3. Sample production

2.4. Characterisations

2.4.1. Fourier transform infrared spectroscopy (FTIR)

2.4.2. Thermogravimetric analysis (TGA)

2.4.3. Morphology

2.4.4. Density

2.4.5. Tension test

2.4.6. Flexion test

2.4.7. Impact test

Table 1 Codes used for the samples produced Code Samples names LLDPE Linear low density polyethylene UF LLDPE + Untreated maple TF LLDPE + 1% MAPE solution modified maple

3.1. Confirmation of maple surface modification

3.1.1. Fourier transform infrared (FTIR) spectroscopic analysis

Table 2 Density of the different raw materials used Samples UF TF MAPE Density (kg m−3) 1437 (7) 1590 (5) 988 (1)

Table 3 LLDPE density as a function of TF and UF content Samples Fibre content (%) Density (kg m−3) LLDPE 0 931 (7) UF composites 10 961 (1) 20 989 (1) 30 1062 (1) TF composites 10 996 (2) 20 1042 (2) 30 1079 (2)

3.3.1. Tensile properties

Footnotes

Acknowledgement

References

Table 1
Codes used for the samples produced

Code Samples names

LLDPE Linear low density polyethylene

UF LLDPE + Untreated maple

TF LLDPE + 1% MAPE solution modified maple

Table 2
Density of the different raw materials used

Samples UF TF MAPE

Density (kg m⁻³) 1437 (7) 1590 (5) 988 (1)

Table 3
LLDPE density as a function of TF and UF content

Samples Fibre content (%) Density (kg m⁻³)

LLDPE 0 931 (7)

UF composites 10 961 (1)

20 989 (1)

30 1062 (1)

TF composites 10 996 (2)

20 1042 (2)

30 1079 (2)