Week 5 Blog Entry

Reflection: 

In the previous lesson, we have learnt and input our knowledge of materials for design for our chemical product. Today's lesson was designing for materials. We learnt how to change a design so that a particular material could be used. In addition, we learnt how the discovery of a new product leads to bringing new uses from the material attributes which could affect design changes and material research for design requirements and vice versa. 

An example given to us was a hair dryer. A hair dryer consists of plastic cover with a bimetallic strip heating element. In order for the plastic to be made suitable as a material for the hair dryer, it uses a thermostat bimetallic strip so that the plastic won't melt under heat. This showed the change (bimetallic strip) in design for materials (plastic hair dryer). 

From this example, we were tasked to do an activity where we had to find a material that can be a direct replacement of another in an existing product without any change in design and finding a use for this material in an existing product that is made possible only by a change of design which is shown below. 

Class:	DCHE2A01	Group:	3
Name of material	Nylon
Chemical Name	Polyamide plastic
General Description	Nylon is a thermoplastic silky material, first used commercially in a nylon-bristled toothbrush in 1938 followed more famously by women’s stockings in 1940. It is made of polyamide (PA) and was the first commercially successful synthetic polymer. Nylon was intended to be a synthetic replacement for silk and substituted for it in many different products after silk became scarce during World War II. It replaced silk in military applications such as parachutes and flak vests and was used in many types of vehicle tires.
General Properties	-Customized highly elastic to viscoelastic grades in a range of different densities and hardness. -Excellent adhesion to surfaces of other polyurethanes, metals and other technical plastics -Very strong and resilient -Damage resistant to chemicals and oil -Does not absorb water -Dries quickly
Opportunities	Nylon is still used today to make parachute canopies due to its elasticity, strength, resistance to mildew and availability. Nylon is ideal for projects that require flexible plastic with the ability to be very lustrous, semi-lustrous or dull.
Discuss among the group how this material can be used as a direct replacement to a material in an existing product without any significant changes in the design.   The product that we chose is a backpack. A typical backpack is made of leather, cotton or canvas which in the long run, would either spoil or be badly damaged.   Nylon is used to replace leather backpack due to its lightweight. Leathers are heavy which can cause injury to the back and spine when the backpack is carried for a long period of time. As leather is heavy, this will increase the cost and make it expensive. In addition, leather has ineffective water resistance and can result to wear and tear overtime. Leather needs higher maintenance as it absorbs oil and stains very quickly which could damage the fabric. Too much water on leather can cause it to become wet due to its permeable nature and as it dries, it will turn hard and stiff which would make users uncomfortable from carrying the backpack. Hence, nylon is preferred instead of leather backpack as it is light, cheap, can resist abrasion and wrinkling and can be washed by machines. Nylon can also be used to replace cotton and canvas backpack. Cotton and canvas are more expensive than nylon and is not very resistant to water. Hence, if there was a spill and the backpack got wet, the contents of the backpack will also get wet. However, with nylon, not only will the backpack be cheaper, but the backpack will also be more resistant to water. Additionally, backpacks made of canvas are not durable as after a few washes, the bag will shrink.
Discuss among the group how this material can be used to enhance the functionality of an existing product through some changes in the design.   The existing product that we chose is a face mask, a nylon layer and a small alteration in the design of the face mask is to enhance the functionality of the product.   A typical surgical mask only filters 45-55% filtration of aerosol particles, while cloth masks have an even lower filtration of 25-38%. Additionally, most masks are layered with the same material which makes the mask harder to breathe in, making it uncomfortable. In order to have better filtration while still being breathable, nylon can be added as another layer for the mask. Adding a layer of nylon boosts the masks performance hence, improving the abilities to filter.   Nylon can provide almost the same amount of filtration as cotton and polypropylene or even better while remaining breathable. Nylon is also water resistant, which means it can repel water droplets from coughs and sneezes, making the user who is wearing the mask safer. Additionally, with nylon being very strong and resilient, the durability of the mask is better.   Although nylon is long-lasting, the nylon layer is more likely to be subjected to wear and tear after many washes. Additionally, the nylon layer would lose its effectiveness in filtering after a while. Therefore, a change in design can be made where there is a pocket to put in the nylon layer. This pocket is built in to accommodate the nylon layer and allows users to change the nylon layer as often as they want. After a certain period, the nylon layer can be switched out to ensure that the effectiveness of the mask is maintained at its best.   As most cloth face masks are not elastic, the addition of nylon makes it more stretchable due to its elasticity. A typical face mask is supposed to be tight to the face so that the air from the surrounding does not make its way to the breathing zone. Hence, the addition of nylon does both the job by keeping the mask tight and sealed to the face as well as providing the right stretchability so that its comfortable for the wearer.                               References: 1.       BYJU'S, n.d. Nylon - Structure, Properties, Uses. [online] Available at: https://byjus.com/chemistry/nylon [Accessed 21 May 2021]. 2.       Godoy, M., 2020. Adding A Nylon Stocking Layer Could Boost Protection From Cloth Masks, Study Finds. [online] Available at: https://www.npr.org/sections/goatsandsoda/2020/04/22/840146830/adding-a-nylon-stocking-layer-could-boost-protection-from-cloth-masks-study-find [Accessed 21 May 2021]. 3.       jeff231, 2019. Examining the Pros and Cons of Canvas Shopping Bags. [online] Available at: https://jeff231.livejournal.com/308772.html [Accessed 20 May 2021] 4.       MAHI Leather. (n.d.). Is Leather Waterproof? Or Water Resistant? [online] Available at: https://mahileather.com/blogs/news/is-leather-waterproof-or-water-resistant#:~:text=Leather%20itself%20is%20not%20well [Accessed 20 May 2021]. 5.     The Spruce. (n.d.). How to Clean and Care for Nylon Clothes. [online] Available at: https://www.thespruce.com/clean-and-care-for-nylon-clothes-1900482#:~:text=Nylon%20fabrics%20are%20usually%20long [Accessed 21 May 2021]. 6.       totebagfactory.com. (n.d.). Canvas vs Leather: How to Choose the Perfect Bag for You. [online] Available at: https://totebagfactory.com/blogs/news/canvas-vs-leather-how-to-choose-the-perfect-bag [Accessed 20 May 2021]. 7.       Who.int. 2021. Coronavirus disease (COVID-19): Masks. [online] Available at: <https://www.who.int/news-room/q-a-detail/coronavirus-disease-covid-19-masks#:~:text=Fabric%20masks%20should%20be%20made,polyester%20or%20polyester%20blend.> [Accessed 21 May 2021]. 8.       carry. (2019). The Ultimate Guide to Backpacks. [online] Available at: https://cultofcarry.org/the-ultimate-guide-to-backpacks/#:~:text=Disadvantages%20of%20a%20leather%20backpack [Accessed 20 May 2021].