Archives for September 2020

Question: Research about plastic, what types of plastic exist? how do you recognize it?

Answer: According to the essay “Plastic: Different Types” from The Hutchinson Unabridged Encyclopedia with Atlas and Weather Guide, I get to know about the basic categories of plastic. Based on the reaction they have when being heated, we can generally divide plastic into two different types. One is thermoplastic, which “soften when warmed, then re-harden as they cool”. The other is thermosets, in contrast, it will “remain rigid once set, and do not soften when warmed”.

The former one includes examples such as some clear plastics used in kitchen utensils or (when expanded into a ‘foam’ by gas injection) in insulation and ceiling tiles; polyethylene or polythene, used for containers and wrapping; and polyvinyl chloride (PVC), which is the most familiar to us, used for drainpipes, floor tiles, audio discs, shoes, and handbags.

The latter one is usually used in electrical insulation and telephone receivers; epoxy resins because of its property that will not be affected by the heat. It is also commonly used in paints and varnishes, to laminate wood, and as adhesives; polyesters, used in synthetic textile fibers and, with fiberglass reinforcement, in car bodies and boat hulls; and polyurethane, prepared in liquid form as a paint or varnish, and in foam form for upholstery and inlining materials (where it may be a fire hazard).

Besides, there are also plastics like Silicones, which usually called Si, and are widely applied in silicone rubber, paints, electrical insulation materials, laminates, waterproofing for walls, stain-resistant textiles, and cosmetics. This is because Si is a kind of chemically inert material, has good electrical properties, and repel water.

And I also find one plastic that really intrigues me. It is a kind of plastics that has shape-memory. In other words, it can be crumpled or flattened and will resume their original shape when heated. They include trans polyisoprene and polynorbornene. The initial shape is determined by heating the polymer to over 35°C and pouring it into a metal mold. The shape can be altered with boiling water and the substance solidifies again when its temperature falls below 35°C.

After acquiring all of this basic knowledge, I find out that plastic-used products are actually everywhere around us, but it is hard for us to recognize them all correctly. In my opinion, one of the methods for us to get to know about them is to do research and make it clear about where plastics may be used in and what specific type of plastic it is. Besides that, recognizing them through the official label may be a wise way. For instance, the label that number 1 wrote inside the recycle logo means PET, which stands for the kind of plastic that is only suitable for plastic bottles containing mineral water or carbonated beverage, etc. I think this is the easiest and most popular way for people to recognize different types of plastics, although some plastics contained in other synthesized materials may still hard to discover.

Question: Read the Jacoby Introduction to Service-Learning, Service Learning Essentials, and answer the following questions. 

1. 1. What is service-learning? What does it mean for different stakeholders? The community you are serving? The faculty teaching the course? The DSS program? And yourself?
   2. Time is very precious in our busy modern-day life. 
      Why are you devoting your precious time to community service?
      

Answer: According to what Barbara Jacoby mentioned in “Introduction to Service Learning”, 

“service-learning as a form of experiential education in which students engage in activities that address human and community needs, together with structured opportunities for reflection designed to achieve desired learning outcomes (Jacoby, 1996c). The hyphen in service-learning symbolizes reflection and depicts the symbiotic relationship between service and learning.” Reflection and reciprocity are the two key elements that make service learning distinguished from other community services. Reflection stands for reviewing and evaluating your own work during the whole service process and learn from that, no matter whether it is something that you achieved or expected to achieve in the future.

Speaking of its significance for different stakeholders in service-learning, for the community we will be serving, it means that they are going to share some of their stories with us and exchange them for something that we create for them. As for the faculty teaching this course, I guess it means to be a leader, or to say a facilitator, to encourage all the students to get themselves involved in the service-learning and actively reflect on themselves so as to learn from the experience. Also, the faculty can also learn from what every student observe and learn from their own experience and possibly combine all of those together to make some more impactful actions to the whole society. For the DSS program, I think it is a good chance to maintain sustainable cooperating relationships with the local community. And last but not least, as for myself, I believe it will be a great chance for me to learn from others, the faculty that we are going to know about, the teammates who will be doing different projects but aiming to the same goal with me, and of course, the professor who know much more than me. Mutually, this will be a hard-won chance to apply what I learn from the classroom to practice and really help someone around us. I think this is really fascinating.

Indeed, time is very precious in our busy modern daily life. But that is exactly where my reason for choosing to devote myself to service-learning lies. Time is precious, not only for me but also for millions of people similar to me. All of us are working hard, busy commuting, and dealing with annoying projects. However, I wonder, if I can use some of my precious time to develop or design something that can help relieve others’ stress in their daily life, or even improve their productivity so as to save their time, I think in that way the time I spent will be much more meaningful.