Wood Composites: Materials, Manufacturing and Engineering

✍ Scribed by Aguilera A., Davim P.J. (ed.)

• Publisher: Walter de Gruyter
• Year: 2017
• Tongue: English
• Leaves: 221
• Series: Advanced Composites
• Category: Library

✦ Synopsis

Wood composites as part of wood engineering materials has been reaching a constant developing trend, being used on a wide range of applications and becoming worldwide as a very promising alternate material face to traditional building materials such as concrete, metal and plastics. In this part of the series are treated aspects among which advances functionalities in laminates, the activation of natural fibres, the natural matrix, and others industrials manufacturing research advances for wood material as composite.
Covering properties and performance of composites, their microstructural characterization, design and manufacture.

✦ Table of Contents

Cover
Half Title
Advanced Composites Series: Volume 6
Also of Interest
Wood Composites: Materials, Manufacturing and Engineering
Copyright
Contents
List of contributing author
1. Introduction of advanced functionalities in laminates for wood-based panels: surface quality evaluation
1.1 The HPL and its manufacture
1.1.1 Introduction
1.1.2 The raw materials
1.1.2.1 Paper
1.1.2.2 Melamine formaldehyde resin
1.1.3 HPL manufacturing process
1.1.3.1 Paper impregnation
1.1.3.2 The pressing process
1.2 HPL properties
1.2.1 Test methods for HPL characterization
1.2.1.1 Assessment of appearance
1.2.1.2 Resistance to surface wear
1.2.1.3 Resistance to abrasion (flooring-grade laminates)
1.2.1.4 Resistance to immersion in boiling water
1.2.1.5 Resistance to dry heat
1.2.1.6 Resistance to climatic shock
1.2.1.7 Resistance to impact by small-diameter ball
1.2.1.8 Resistance to scratching
1.2.1.9 Resistance to staining
1.2.1.10 Resistance to UV light (exterior-grade laminates)
1.2.1.11 Resistance to artificial weathering (exterior-grade laminates)
1.2.1.12 Resistance to cigarette burns
1.2.1.13 Gloss level
1.2.1.14 Determination of color of HPL
1.2.2 HPL specifications
1.3 Upgrading HPL characteristics
1.3.1 Mar resistance
1.3.2 Abrasion resistance
1.3.3 Resistance against strong chemicals
1.3.4 Weathering resistance
1.3.5 Self-healing properties
1.3.6 Postformable laminates
1.3.7 Dirt repellence
1.3.8 Antibacterial action
1.3.9 Thermal comfort
1.3.10 Phosphorescence
References
2. Activation of natural fibers using physical routes: Applications for composites materials
2.1 Introduction
2.1.1 Reinforcements
2.1.2 Polymer matrix
2.2 Surface activation of cellulosic fibers: Wave and radiation technologies
2.2.1 Ultraviolet (UV) technology
2.2.1.1 Basic principles
2.2.1.2 Treatment effects on fibers
2.2.1.3 Applications for composite materials
2.2.2 Plasma technologies
2.2.2.1 Basic principles
2.2.2.2 Treatment effects on fibers
2.2.2.3 Applications for composite materials
2.2.3 Corona technologies
2.2.3.1 Basic principles
2.2.3.2 Treatment effects on fibers
2.2.4 High energy radiations technologies
2.2.4.1 Basic principles
2.2.4.2 Treatment effects on fibers
2.2.4.3 Applications for composite materials
2.3 Surface activation of cellulosic fibers: Physico-chemical technologies
2.3.1 Ultrasound technologies
2.3.1.1 Basic Principles
2.3.1.2 Treatment effects on fibers
2.3.1.3 Applications for composite materials
2.3.2 Solvent technologies
2.4 Surface activation of cellulosic fibers: Thermomechanical technologies
2.4.1 Steam explosion (SE) technology
2.4.1.1 Basic principles
2.4.1.2 Treatment effects on fibers
2.4.1.3 Applications for composite materials
2.4.1.4 Application for fiberboards
2.5 Surface activation of cellulosic fibers: Other technologies
2.5.1 Steam technologies
2.5.2 Carding technologies
2.6 Conclusions
References
3. Natural matrix/non wood natural fibers composites
3.1 Comparison with UD fiber-reinforced composites
3.2 Water resistance of the composites
3.3 Influence of the layers on the composite properties
References
4. Ultrasonic press control and evaluation of wood-based composite panel properties
4.1 Introduction
4.2 Background
4.2.1 Assessment methods
4.2.1.1 Nonacoustic methods
4.2.1.2 Ultrasonic methods
4.3 Main focus of this chapter
4.3.1 Press control
4.3.1.1 AU equipment
4.3.1.2 Ultrasonic output during pressing
4.3.1.3 Effects of board variables
4.3.2 On-line measurement of board properties
4.4 Future research directions
4.4.1 Press control
4.4.2 On-line air coupling
4.4.2.1 Air-coupled transducers
4.4.2.2 Transducer arrangements
4.4.3 Preliminary results from single-sided testing
4.5 Conclusions
References
Further reading
5. Reconstituted composite from crop stalks
5.1 Introduction
5.2 Characteristics of crop stalks
5.2.1 Cotton stalk
5.2.2 Tobacco stalks
5.2.3 Soybean stalks
5.2.4 Corn stalks
5.2.5 Capsicum pepper stalks
5.3 The manufacturing process
5.3.1 Raw material preparation
5.3.2 Stalk softening and combing
5.3.3 Crop stalk drying
5.3.4 Crop stalk sizing
5.3.5 Crop stalk forming
5.3.6 Hot pressing
5.3.7 End products
5.3.8 Properties of the composite
5.3.9 Stalk composite appearance and other performance
5.4 Curing mechanism of urea-formaldehyde resin in stalk composite
5.4.1 Infrared spectroscopy before curing
5.4.2 Infrared spectroscopy after curing
References
6. Wood welding without adhesives
6.1 Systems of frictional wood welding
6.1.1 Linear vibration welding
6.1.2 High speed rotation dowel welding
6.1.3 Bamboo welding
6.2 Applications of wood welding
6.3 Exterior and semiexterior applications
6.4 Interior applications
References
7. Surface quality of mechanically processed wood
7.1 General considerations on wood formation
7.2 Surface evaluation
7.2.1 Quality assessment by feed per tooth (fz)
7.2.2 Quality assessment by the depth of the cycloid arc (t)
7.2.3 Quality assessment by visual analysis
7.2.4 Quality assessment by surface roughness
7.2.5 Quality assessment by sunset laser
References
Further reading
8. Strategies to reduce formaldehyde emissions from wood-based panels: Impact on physico-mechanical properties and machinability
8.1 Strategies to reduce formaldehyde emissions from wood-based panels
8.1.1 The concern about formaldehyde and current status
8.1.2 Current test methods for determining formaldehyde emissions
8.1.2.1 Introduction
8.1.2.2 Perforator method
8.1.2.3 Chamber method
8.1.2.4 Gas analysis
8.1.2.5 Desiccator method
8.1.2.6 Flask method
8.1.2.7 Other methods
8.1.3 Formaldehyde emission classes
8.1.4 Strategies to reduce formaldehyde emissions from wood-based panels
8.1.4.1 Formaldehyde emission from wood-based panels
8.1.4.2 Strategies to reduce formaldehyde emissions
8.1.4.3 Formaldehyde scavengers
8.2 Impact of formaldehyde-reducing strategies on formaldehyde emission and physico-mechanical properties
8.2.1 Physico-mechanical properties of wood-based panels
8.2.2 Case studies
8.3 Impact of formaldehyde-reducing strategies on machinability
8.3.1 Introduction
8.3.2 Case studies
8.4 Future perspectives
References
Index