4.2d: Plastics (Part 2)

Thermoplastics

Thermoplastics are liner chain molecules, sometimes with side bonding of the molecules but with weak secondary bonds between the chains. Between the long chain molecules are secondary bonds which are weak forces of attraction between the molecules.

Thermoplastics can be heated and reformed. They can be reused (in comparison to thermosetting plastics).

Thermoplastic polymer structure

Production of thermoplastics

Characteristics of thermoplastics include:

• Ductile
• Low stiffness -squishy water bottles for example
• Easily injected into a mold
• Can be reshaped after heating
• Easily and cost effectively manufactured

Types of thermoplastics include: PP (Polypropene), PE (Polythene), HIPS (High Impact PolyStyrene), ABS (Acrylonitrile butadiene styrene), PET (Polyethylene terephthalate), and PVC (Polyvinyl chloride

Uses of thermoplastics:

Thermosetting plastics

Thermosets are linear chain molecules but with strong primary bonds between adjacent polymer chains (or cross links). This gives thermosets a rigid 3d structure.

Thermosetting plastics can only be reformed once - the shape is permanently set and is permanently locked.

Thermosetting plastic polymer structure

Production of thermosetting plastics

Characteristics of thermosetting plastics include:

• Higher stiffness
• Higher strength than thermoplastics 
• Cannot be reheated and remoulded - it will usually char

Types of thermosetting plastics include: Polyurethane, Urea-formaldehyde, melamine resin, and epoxy resin

Uses of thermosetting plastics:

Recovery and disposal of plastics

Nearly all types of plastics can be recycled, however the extent to which they are recycled depends upon technical, economic, and logistic factors. as a valuable and finite resource, the optimum recovery route for most plastic items at the 'end-of-life- is to be recycled, preferably back into a product that can then be recycled again and again and so on. 

• Thermoplastics can be easily recycled
• Thermoplastics come in a range of chemical compounds and therefore need to be sorted for recycling
• Thermosets are not so easy (and expensive to do so).
• Often get sent to the landfill

Example - Plastics can be recycled into clothes (recycled polyester)

     BENEFITS OF RECYCLING:

• sustainable source of raw materials
• reduces environmental impact of plastic-rich products 
• minimizes the amount of plastic being sent to the landfill sites
• avoids the consumption of the Earth's oil stocks
• consumes less energy than producing new, virgin polymers
• encourages a sustainable lifestyle among children and young adults

Bioplastics

To reduce the problems of disposing of plastics they can be designed to be biodegradable, known as bioplastics. These are plastics derived from renewable sources, such as vegetable fats and oil, corn starch, pea starch or microbiota. 

Production of oil based plastics tend to require more fossil fuels and to produce more greenhouse gasses than the production of bio-based polymers. 

Some, but not all, bioplastics are designed to biodegrade.

Process of bioplastic production

Helpful links:
http://www.bbc.co.uk/schools/gcsebitesize/design/resistantmaterials/materialsmaterialsrev3.shtml

Portfolio Skills: Cubes/Cuboids

Drawing two point perspective cubes and cuboids

Adding design features, enhancing aesthetics

4.2d: Plastics

4.2d
Plastics
Most plastics are produced from petrochemicals. Motivated by the finiteness of oil reserves and threat of global warming, bio-plastics are being developed. these plastics degrade upon exposure to sunlight, water or dampness, bacteria, enzymes, wind erosion and in some cases pest or insect attack, but in most cases this does not lead to full breakdown of the plastic.

     History of Plastics

• Natural plastics - these are naturally occurring materials that can be said to be plastics because they can be easily shaped and moulded by heat.

Pine tree resin jewelry

Wax used for sealing letters

• Semi synthetic plastics - these are made from naturally occurring materials that have been modified or changed but mixing other materials with them. 
• Bakelite - was initially used in electrical goods; is cheap and easy to manufacture and gave a consistently high quality product.
• 
• Synthetic plastics - These are materials that are derived from breaking down, or 'cracking' carbon based materials, usually crude oil, coal, or gas, so that their molecular structure changes.

Synthetic plastic products

     Raw materials for plastics

Crude oil is used as a raw material for most plastic manufacture

• plastics derive from natural materials such as crude oil , coal and natural gas (crude oil being the most prominent raw material used. 

Synthetic plastic products

• all plastics are based on polymers and they are created by bonding molecules together. The terms monomer and polymer are very important in the plastics industry - a monomer is a relatively small molecule that can chemically bond to other monomers, forming a polymer.

Portfolio Skills: Cylinders

Sketches of cylinders on pen and paper

INSTRUCTIONS ON HOW TO DRAW CYLINDERS:

7.5: Beyond Usability: designing for pleasure & emotion

7.5
Beyond Usability: Designing for pleasure and emotion
Usability is not the only factor for a designer to consider; products can be designed to evoke pleasure and emotion.

     FOUR-PLEASURE FRAMEWORK: 

• Socio-pleasure: 

• Socio-pleasure can be derived from social interaction and are concerned with pleasures derived from social signifiers of belonging, social-enablers and other social self-identification factors. 
• Examples include email, internet, and mobile phones that facilitate communication between people.

• Physio-pleasure:



The new car smell is an example of physio-pleasure

• Is derived from the feel of a product during use from a human's senses, such as the smell, taste, feel of the object. 
• Examples include: wearing a silk garment, taste of a food, smell of leather, a new car, coffee, or freshly baked bread

• Psycho-pleasure:
• Is derived from the cogonanitive demands of using a product or service and the emotional reactions engendered through the experience of using it 



The Behmor coffee maker is advanced and convenient

• Examples include: products that were improved or redesigned from the previous type

• Ideo-pleasure
• Ideo-pleasures are pleasures that are linked to our ideals, aesthetically, culturally, and otherwise to satisfy people's tastes, values and aspirations. 



Organic products embodies healthy food

• Examples include a product made from biodegradable materials that might be perceived as embodying the value of environmental responsibility.

     Design for emotion:

• Visceral design: Design that speaks to people's nature in terms of how the expect products and systems to function and how they expect to interact with them
• Reflective Design: Design that evokes personal memory focussing on the message, culture and meaning or the use of the product
• Behavioural design: Focussed on use and understanding,  this considers how people will use a product, focussing on functionality
• https://usabilla.com/blog/designing-usability-just-isnt-enough/

     The attract-converse-transact (ACT) model

The ACT model is a framework for creating designs that improve the relations of users with a product and intentionally trigger emotional responses.

• The attract part of the model is aesthetics oriented
• The converse part of the model is interaction oriented
• The transact part of the model is function oriented

4.2b: Timber

4.2b
Timber
Timber is a major building material that is renewable and uses the Sun's energy to renew itself in a continuous cycle.

Characteristics of Natural Timber
There are two types of natural timber, called hardwood and softwood. These names do not refer tot he properties of the weed necessarily as some softwoods can be relatively hard and some hardwoods can possess the mechanical properties of a softwood

     Structure of Natural Timber

Wood Structure of Hardwood and Softwood

• Natural timber is a natural composite material compromising celulose-fibres in a lignin matrix

     Moisture content of natural timber

• When living trees are cut down the timber is of very little use in engineering, product design and so on. This is due to the moisture of the wood. Most of this moisture needs to be removed and a equilibrium moisture content achieved

     Seasoning

• is the commercial drying of timber which reduces the moisture content of the wood, making the timber highly usable. Methods include kiln seasoning, air-drying, and kiln-drying

     Timber defects

• Warping is the distortion in wood caused by uneven drying, which results in the material bending or twisting
• Bowing is the warping along the length of the face of the wood 
• Twisting is the warping where the two ends of a material do not lie on the same place

     Hardwood

• hardwoods come from deciduous (meaning that they lose their leaves in the wintertime) trees. 
• the trees can take up to a hundred years to go (slow growth), making it more dense and more expensive
• not all hardwoods are hard, such as balsa which is used for model planes
• Hardwoods are sold by the cubic metre and sawn depending on what the customer want
• Deciduous trees grow in the temperate, subtropical and tropical regions of the world
• Types include:

  

  Mahogany wood

   

  

  Types of hardwood

     Softwood

• generally come from coniferous trees which are evergreen
• can often be harder than hardwood
• Softwoods grow faster than hardwoods and so are cheaper and are easier to work with as their are softer than hardwoods
• Coniferous trees grow tall and straight, providing for long planks of wood
• more environmentally friendly to use softwood rather than hardwood because it takes 3 times faster to grow, is more sustainable
• grown in temperate regions
• Types include:

  

  Types of softwood

Characteristics of man-made timbers
Manufactured boards are timber sheets which are produced by gluing wood layers or wood fibres together. Manufactured boards often made use of waste wood materials. Manufactured boards have been developed mainly for industrial production as they can be made in very large sheets of consistent quality. Boards are available in many thicknesses but commonly 3, 6, 9, 12, 15, 18, 20, and 25 mm.


      Man-made timbers

• come in sheet material
• made from particles of wood, mixed with a resin/glue to make the sheets (made from the by-products of timber)
• not recyclable afterwards, possible to reuse
• the dust produced from cutting the dust is not particularly good for you (you should be wearing a mask)
• Tensile strength depends on the man made timber, plywood has high tensile strength, particle board and MDF are very low
• could be used for flooring, boarding up a window, a filler for a table top for example
• some man-made timbers are resistant to damp environments, depending on the type
• Longevity - depending on type
• Aesthetic properties  - appears like real wood
• is a sufficient alternative to real timber as it is becoming scarce and more expensive
• Types include:
  
• MDF - Smooth, even surface. Easily machined  and painted or stained. Also available in water and fire resistant forms. Used mainly for furniture and interior panelling due to its easy machining qualities. Often veneered or painted
• ADVANTAGES: cheaper at cost and inexpensive, saves trees as it is recycling process, easy to color, no knots or kinks, easy to cut and drill without damaging
• DISADVANTAGES: comparatively weaker than wood, furniture doesn't last long, can crack or split under extreme stress, absorbs water quicker than wood, doesn't take nails and screws easily, contains VOC that can cause irritation to lungs and eyes, dust produced during the manufacture of MDF is very harmful to breathing.
• Plywood - A very strong board which is constructed of layers of veneer or piles which are glued at 90 degrees to each other. Laminated material meaning that it is made out of many layers (odd numbers) - grains are put at opposite from one another:
• ADVANTAGES: the alteration of the grains done inside plywood (called cross graining) makes the material have strength, gives it stability, has a reduced possibility of bending, it is lighter than hard wood, has an ecological importance
• DISADVANTAGES: weaker than wood, not durable like wood, not always easy to sculpture, long-term can get attacked my insects, surface of plywood (if not painted well) can be peeled off
• Chipboard/Particle board - made from chips of wood glued together. Usually veneered or covered in plastic laminate (for aesthetic or practical purposes)
• ADVANTAGES: cost effective,  is sold at low prices, provides smooth and flat surface and is aesthetically attractive, does not dent or distort easily, can be easily transported and handled, minimal maintenance
• DISADVANTAGES: low strength, in presence of moisture particle board expands and warps, discoloration can occur, cannot support heavy loads, can be toxic (resin can break down over time)

Treating and finishing timbers

Timber is seasoned as a part of its preparation for commercial use. This process reduces the moisture content so that it becomes workable. The remaining moisture, albeit small, means that the wood never really stabilises and continues to swell and shrink, with humidity and temperature variations. Timber treatments and finishes are used to protect, enhance and improve the mechanical properties.

1. Timber treatments

Timber treatments are an additive preservative to improve the timber's resistance to attack and improve its durability.

(Examples of wood preservatives)

2. Timber finishes

Timber finishes are applied to the surface of the timber and is usually carried out to achieve one or both of the following reasons :

• Aesthetics - to improve the materials' natural beauty 
• Function - to protect it from environmental impact, heat, and moisture 
• Examples of timber finishes are varnish/estapol, finishing oils, and wood wax.

Recovery and disposal of timber

Timber is one of the most renewable and 'earth friendly' materials available which makes the principle and practical aspect of recovery and recycling quite straightforward.

• Recovery and recycling - turning waste timber into usable products. 
• Uses for recycled waste wood include traditional feedstock for the panel board industry, which still accounts for the majority of recycled wood. Other uses include animal beddings, equestrian and landscaping surfaces, play areas and filter beds.

7.4: Strategies for UCD

7.4
Strategies for UCD
Users have a central role in evaluating whether the product meets their wants and needs. There are strategies that we use to conduct research.

PRIMARY AND SECONDARY RESEARCH
     Difference between primary/secondary research 

• Primary - collection and analysis of original information. Examples of primary research include user trial, user research, field trials, product analysis, and observation
• Secondary - use of existing information (using the internet) examples include literature searches and web searches
  

QUALITATIVE AND QUANTITATIVE RESEARCH
     Difference between qualitative and quantitative research

• Qualitative - subjective (measures how and why people behave)
• Quantitative - measurable (more focused on who, what , where , and when)

  

  differences between qualitative and quantitative measures

     Field research

• a first hand observation of customer's user experiences, conducted in the user's environment
• can be field trials, ethnographic interviews, or observations in the real world
• field researches conduct takes place in the participant's environment - such as a homework, store, bank or hospital.
• it is qualitative as it is an observation and not something that can be measured
• biggest downside to field research is the cost, as it could get very expensive to conduct specialised tests
  

     Method of extremes

• this method requires sample users selected to represent the extremes of the user population plus one or two intermediate values.
• is used to define the range of a user population
• Deciding whether to use the 5th, 50th, or 95th percentile value depends on what you are designing and who you are designing it for.

  

  Examples of design situations

  
  

  

  Designing for a range of people
  

  

     Observation, interviews, and focus groups

• user trial where the intended client uses the product and the expert observes - can be in the field (natural environment) or in a lab (controlled environment)
• Advantages include the unveiling of usability issues
• Disadvantages include the difficulty of analyzing data



Advantages and disadvantages of observations



Advantages and disadvantages of focus groups 

• Focus groups are groups of people that share similar traits that are questioned to get results from a specific group; they are a facilitated sessions with a number of individuals from your target audiences brought together to discuss specific elements of your digital offering and customer service



Design process regarding observation

     Questionnaires

• the user only answer questions posed to them about a product or context, but they do not have the actual product nor can they test the actual product
  

     Affinity diagramming

• a graphical tool that identifies a general theme to collect facts, opinions and ideas, has brainstorming purposes



Organising thoughts into patterns



• Data is expressed in creating clusters and groups of common information.
  

     Participatory design, prototype and usability testing sessions

• involving target users in the design process, seeks to include the intended users either in the research, concept, design or production of an outcome. It does not just ask users opinions on design issues, but actively involves them int he design and decision-making process.
• actively involving all stakeholders (eg.employees, partners, customers, end users) in the design process to help ensure the result meets their need and is useable
• Paper prototyping is a variation of usability testing and example of participatory design where representative users perform realistic tasks by interacting with a paper version of the interface - the benefits include that it is cheap and quick and easily disposable

Example of of a paper prototyped phone

     Natural environments and usability laboratories

• Usability labs are environments where users are studied taking part in focus groups or some form of participatory design. Usability testing is carried out in a usability laboratory.
• Usability labs are set up for testing , as they are more controlled.
• Natural environments are environments in which the user is already comfortable and familiar with, as opposed to a usability lab. The user will be allowed to test products in the comfort of their homes or place of work and monitor them remotely.

     Testing houses versus usability laboratories

• Advantages of natural environments: solicit data from real and intended contexts, usability is tested in the intended environment.
• Disadvantages of natural environments: biased opinions from the observers and mostly qualitative data is collected.
• Advantages of usability labs:

Helpful links:
http://www.designkit.org/methods