The central theme of our education is often based on the conviction that practice
follows scientific understanding. But it is more common that practice and its
surprising and exceptional results stimulate the scientific quest and only then
allows, in turn, scientifically inspired progress in practice. This is most evident in
the way in which macromolecular substances and our interactions with them
have changed human life. Chemistry is one of the great steps in our conceptual
development (and we should not forget physics), but the experience was first and
the chemical understanding of matter, and particularly of macromolecular matter,
only evolved after many millennia of beneficial experimentation with and use of
macromolecular substances. Here we would like to substantiate this fact once more.
First, however, a cautionary note: the ideas presented here are not original nor
based on the author’s work. What you read in the following is entirely derivative
and rests exclusively on the publications of others. The author attempts to cite the
work of the major contributors and the reviews from which he also learned, but
admits that he has left out many great contributions and conceptual creations. The
reviewers that most influenced him are Paul J. Flory [1], Herbert Morawetz [2, 3],
and Dietrich Braun [4].
1 How Macromolecular Substances Came Into Use
Natural macromolecular materials have been in use since before Homo sapiens
evolved. At first, these were natural substances, available for use without
any intervention. Our ancestors and mankind from its beginnings have protected
themselves with skins and weavings, used fibers and sticks, and employed bitumen
for gluing and sealing. Macromolecular manmade materials have a shorter history,
but still date back to before the advent of Homo sapiens, i.e., to species existing
before us (see [5] and its excellent bibliography!). The substance possibly used
earliest is birch bark pitch, an adhesive (and arguably medical chewing substance
[6]) made by controlled heating of white birch bark under exclusion of air [7], that
was invented by Homo erectus or Neanderthal man, certainly at least 80,000 years
[8, 9] and possibly more than 180,000 years ago [10, 11], and was ubiquitously
produced globally. It is a “product of ancient chemical technology” [12]. Homo
sapiens made a wide range of adhesives by artisanal production more than 70,000
years ago in South Africa [13, 14].
Other natural products were also converted into useful materials [15]. Development and use was worldwide and left its traces in all high cultures, from which
artifacts are still available. Adhesive bonding apparently was everywhere the first
use. There are reports of discoveries in the early Middle Eastern societies such as
Assyria, Mesopotamia, Babylon, etc. (see [16] and sources cited therein), as well as
Rome [17], and ancient Egypt [18] that demonstrate many parallels but also show
interesting differences. With time, the use of macromolecular substances evolved
from adhesives to shapes; at first as inlay material (e.g., for weapons and jewelry in
the Bronze Age [19]), then as material from which entire shapes could be
62
U.W. Suter
follows scientific understanding. But it is more common that practice and its
surprising and exceptional results stimulate the scientific quest and only then
allows, in turn, scientifically inspired progress in practice. This is most evident in
the way in which macromolecular substances and our interactions with them
have changed human life. Chemistry is one of the great steps in our conceptual
development (and we should not forget physics), but the experience was first and
the chemical understanding of matter, and particularly of macromolecular matter,
only evolved after many millennia of beneficial experimentation with and use of
macromolecular substances. Here we would like to substantiate this fact once more.
First, however, a cautionary note: the ideas presented here are not original nor
based on the author’s work. What you read in the following is entirely derivative
and rests exclusively on the publications of others. The author attempts to cite the
work of the major contributors and the reviews from which he also learned, but
admits that he has left out many great contributions and conceptual creations. The
reviewers that most influenced him are Paul J. Flory [1], Herbert Morawetz [2, 3],
and Dietrich Braun [4].
1 How Macromolecular Substances Came Into Use
Natural macromolecular materials have been in use since before Homo sapiens
evolved. At first, these were natural substances, available for use without
any intervention. Our ancestors and mankind from its beginnings have protected
themselves with skins and weavings, used fibers and sticks, and employed bitumen
for gluing and sealing. Macromolecular manmade materials have a shorter history,
but still date back to before the advent of Homo sapiens, i.e., to species existing
before us (see [5] and its excellent bibliography!). The substance possibly used
earliest is birch bark pitch, an adhesive (and arguably medical chewing substance
[6]) made by controlled heating of white birch bark under exclusion of air [7], that
was invented by Homo erectus or Neanderthal man, certainly at least 80,000 years
[8, 9] and possibly more than 180,000 years ago [10, 11], and was ubiquitously
produced globally. It is a “product of ancient chemical technology” [12]. Homo
sapiens made a wide range of adhesives by artisanal production more than 70,000
years ago in South Africa [13, 14].
Other natural products were also converted into useful materials [15]. Development and use was worldwide and left its traces in all high cultures, from which
artifacts are still available. Adhesive bonding apparently was everywhere the first
use. There are reports of discoveries in the early Middle Eastern societies such as
Assyria, Mesopotamia, Babylon, etc. (see [16] and sources cited therein), as well as
Rome [17], and ancient Egypt [18] that demonstrate many parallels but also show
interesting differences. With time, the use of macromolecular substances evolved
from adhesives to shapes; at first as inlay material (e.g., for weapons and jewelry in
the Bronze Age [19]), then as material from which entire shapes could be
62
U.W. Suter