Biopolymers and Biotech Admixtures for Eco-Efficient Construction Materials

Fernando Pacheco-Torgal, Volodymyr Ivanov, Niranjan Karak, Henk Jonkers

• Publisher: Woodhead Publishing
• Year: 2016
• Print ISBN: 9780081002148
• eBook ISBN: 9780081002094
• Topic: Technology & Engineering
• Subtopic: Architecture Methods & Materials
• Index: Technology & Engineering

Since 1930 more than 100,000 new chemical compounds have been developed and insufficient information exists on the health assessment of 95 percent of these chemicals in which a relevant percentage are used in construction products. For instance Portland cement concrete, the most used material on the Planet (10.000 million tons/year that in the next 40 years will increase around 100 %) currently used in around 15% of total concrete production contains chemicals used to modify their properties, either in the fresh or hardened state. Biopolymers are materials that are developed from natural resources. They reduce dependence on fossil fuels and reduce carbon dioxide emissions. There is a worldwide demand to replace petroleum-based materials with renewable resources. Currently bio-admixtures represent just a small fraction of the chemical admixtures market (around 20%) but with environmental awareness for constituents in construction materials generally growing (the Construction Products Regulation is being enforced in Europe since 2013), the trend towards bio-admixtures is expected to continue. This book provides an updated state-of-the-art review on biopolymers and their influence and use as admixtures in the development of eco-efficient construction materials. - Provides essential knowledge for researchers and producers working on the development of biopolymer-modified construction materials - Discusses the various types of biopolymers currently available, their different production techniques, their use as bio-admixtures in concretes and mortars and applications in other areas of civil engineering such as soil stability, wood preservation, adhesives and coatings - All contributions are made from leading researchers, who have intensive involvement in the design and use of biopolymers in construction materials

1

Introduction to biopolymers and biotech admixtures for eco-efficient construction materials

F. Pacheco-Torgal University of Minho, Guimarães, Portugal

Abstract

This chapter introduces important problems related to crude oil, the main feedstock of most polymer-based materials. These problems include interstate wars and environmental disasters. The latter is the most worrisome, such as the recent Deep Water Horizon oil spill that released approximately 780 million liters of crude oil on the Gulf of Mexico. Some historical examples on the use of bio-admixtures in construction materials are presented. The importance of biopolymers and biotech admixtures for eco-efficient construction materials is summarized. A brief review on the role of promising biotech-based materials, like cellulose nanocrystals for eco-efficient construction, is given. An outline of the book is also given.

Keywords

Biopolymers; Biotech admixtures; Cellulose nanocrystals; Eco-efficient construction materials; Oil; Polymer industry

1.1. Introduction

For more than half a century the fossil fuel industry has provided the resources for the polymer industry. Independently of the “Peak Oil” never ending discussion (Chapman, 2014), the future scarcity of petroleum resources (Sorrell et al., 2012) is a fact that must be faced sooner or later. Moreover, it does not matter very much that the shale oil euphoria could turn the USA into the world's largest oil producer (Morse, 2014).

Granting the fact, one believes that oil scarcity is not the major issue to be addressed concerning this nonrenewable resource. In the short term, interstate wars and environmental disaster are the major issues. Never before has a commodity triggered so many armed conflicts (Black, 2012). Moreover, since 1973, at least one-quarter of all interstate wars were connected to oil (Verbruggen and van de Graaf, 2013).

States with large oil reserves and unstable political governments tend to instigate conflicts at a rate three and a half times that of comparable states with stable governments and without oil (Colgan, 2013, 2014).

Most importantly, environmental disasters are caused by oil spills like the 1979 Ixtoc 1 off-shore oil rig blowout, which during nine months released 530 million liters of crude oil into the Gulf of Mexico (Jernelov and Linden, 1981; Patton et al., 1980) causing massive damage to maritime ecosystems (Soto et al., 2014). Add to that the 1989 Exxon Valdez oil tanker “small” episode (41 million liters of crude oil) in Alaska that killed hundreds of thousands of seabirds, billions of fish eggs, and many whales and seals (Alford et al., 2014; Malakoff, 2014), and the 2010 British Petroleum (BP)-owned Deep Water Horizon oil spill, which released approximately 780 million liters of crude oil into the Gulf of Mexico (Atlas, 2011). These represent the dark side of crude oil production for which no life-cycle analysis can account.

The latter was considered the worst environmental disaster to have occurred in the USA. According to Costanza et al. (2010), this environmental tragedy was responsible for an almost complete shutdown of the $2.5 billion per year Louisiana fishing industry and was also responsible for a $34–$760 billion loss of ecosystem services in the Mississippi River delta alone. This value exceeds even BP total market value and still raises environmental and public health concerns (Ortmann et al., 2012; Wise et al., 2014; Drescher et al., 2014; Gill et al., 2012).

The chronology of other crude oil-related disasters can be seen at Infoplease (2014). In addition, the increase in crude oil transport by oil tankers has led to an increase in collision risk (Morgan et al., 2014).

Because oil exploration is moving into ever-deeper water and into stormier and icier seas, it means increased risks (Jernelov, 2010).

According to Sällh et al. (2015), the share of offshore oil production is expected to increase from 33% to 48% by 2030. This means that the risk of new environmental disasters related to oil production will also increase.

All of the foregoing clearly justifies the search for new and biodegradable polymers based on renewable feedstock.

Recent years have seen a tremendous increase in the number of publication citations on biobased polymers (around 1000% in the last 10 years). However, the fact is that these materials still constitute only a very small fraction of the polymer industry (Babu et al., 2013).

Biopolymers include polymers from agro-resources (polysaccharides, cellulose, starch, chitin, chitosan, and alginates), from microorganisms by fermentation (polyhydroxyalkanoates, such as polyhydroxybutyrate) and from biotechnology via conventional synthesis (polylactides (PLA), polybutadiene succinate, biopolyethylene (PE), polytrimethylene terephthalate, poly-p-phenylene) (Avérous and Pollet, 2012). Although some are biodegradable, that is not always the case, like, for instance, PE.

It is clear that the farming practices used to grow biobased feedstock including the fuel required for plowing, harvesting, manufacture, and transport, and the use of herbicides and pesticides, can also have environmental impacts as high as those of petrochemical-based polymers (Yates and Barlow, 2013). However, biopolymers are not associated with armed conflicts, nor are they responsible for large environmental disasters that so often occur in crude oil extraction and transportation. Besides, the reuse of agricultural and biomass waste will contribute to the environmental advantages of biopolymers over traditional petroleum-based polymers (Gopalakrishnan et al., 2012, 2013; Hottle et al., 2013).

1.2. Biopolymers and biotech admixtures for eco-efficient construction materials

Bio-based admixtures have been used in construction materials for centuries. The use of air lime mortars with the addition of vegetable fat goes back to Vitruvius of the Roman Empire (Albert, 1995).

The Romans also had recognized the role of bio-admixtures to improve their building materials; for example, dried blood was used as an air-entraining agent, whereas biopolymers such as proteins served as set retarders for gypsum (Plank, 2003).

The Chinese already have used egg white, fish oil, and blood-based mortars during the construction of the Great Wall due to their imperviousness (Yang, 2012).

In 1507, mortars based on lime mixed with small amounts of vegetable oil added during the slaking process were used in the construction of the Portuguese fortress, “Nossa Senhora da Conceição,” located on Gerum Island, Ormuz, Persian Gulf (Pacheco-Torgal and Jalali, 2011). More than 300 years after the fortress construction, A. W. Stiffe, a Lieutenant of the British Navy, visited the interior of the fortress and made a description of its conservation status for Geographical Magazine. He stated that “The mortar used was excellent, and much more durable than the stones” (Rowland, 2006).

The twentieth century became the age of admixtures, the history of which started in the 1920s with the introduction of lignosulfonate, a biopolymer, for Ordinary Portland Cement (OPC) concrete plasticization, the first functional polymer used in construction on a large scale (Plank, 2004).

OPC concrete, a typical civil engineering construction material, is the most used material on Planet Earth. Its production reaches 10,000 million tons/year and in the next 40 years will increase around 100% (Pacheco-Torgal et al., 2013b).

Currently, around 15% of the total OPC concrete production contains chemical admixtures to modify their properties, either in fresh or hardened state. Concrete super plasticizers based on synthetic polymers include melamine, naphthalene condensates, or polycarboxylate copolymers to improve their workability, strength, and durability. Examples of biopolymers used in concrete include lignosulfonate, starch, chitosan, pine root extract, protein hydrolysates, or e...

Table of contents

• Cover image
• Title page
• Table of Contents
• Related titles
• Copyright
• List of contributors
• Woodhead Publishing Series in Civil and Structural Engineering
• Foreword
• 1. Introduction to biopolymers and biotech admixtures for eco-efficient construction materials
• Section One. Production of biopolymers for eco-efficient construction materials
• Section Two. Biopolymers and biotech admixtures in cement and mortars
• Section Three. Biopolymers and biotech admixtures in concrete
• Section Four. Other biopolymer applications
• Index