Plastics Instructional Module II

Properties of Matter

 

 

1.     Activity – They’re Everywhere!

    1. Teacher Information
    2. Student Worksheets

 

2.     Activity – They’re in my House!

    1. Teacher Information
    2. Student Worksheets

 

3.     Hand-out – Resin Classification Codes

 

4.     Activity – Classification of Plastic Containers

    1. Teacher Information
    2. Student Worksheets

 

5.     Lab – Plastics Analysis Lab

    1. Teacher Information
    2. Student Worksheets

 

6.     Activity – Assessment of Plastic Container Classification

    1. Teacher Information
    2. Student Worksheets

 

  1. Common Plastic Properties and the Molding Process
    1. Teacher Information

 

8.     Activity – Which Polymer Should We Use?

    1. Teacher Information
    2. Student Worksheets

 

9.     Activity – Polymer Trivia

    1. Teacher Information

ACTIVITY – THEY’RE EVERYWHERE!

 

 

OBJECTIVES:

      Demonstrate to the student that:

1.     plastics are found everywhere in our environment,

2.     there are a variety of plastics which exhibit different physical properties,

3.     plastics with specific properties are particularly useful in different situations.

 

PURPOSE:

      The student will make a list of plastic objects found in the classroom or home.   Encourage many different unusual responses.  After compiling the list, the student will attempt to write a statement describing each plastic object’s color, hardness, flexibility, transparency, clarity, and strength.  Students may work individually or in small groups to complete this activity.

 

SUGGESTED VOCABULARY:

     

                  natural polymer                       transparent

                  translucent                               rigid

                  opaque                                     flexible

                  physical properties                  plastic

                  mechanical properties             synthetic polymer

 

OUTCOMES:

 

      After the worksheet is completed, have individual students or the group spokesperson share their answers with the class.  Write the different items with their observed physical properties on the board.  Use specific vocabulary terms in discussing these.  Ask the class to reach a consensus on whether or not plastics are important to us in out daily routine.  Ask students to compare and contrast the different physical properties of items identified by members of the class.

NAME:____________________________DATE:_____________

 

 

 

ACTIVITY – THEY’RE EVERYWHERE!

 

 

 

 

DIRECTIONS:  Name five things in this room that are made from plastic.  Answer the following questions about each item:

1.     Name something in this room that’s made from plastic.

2.     What color is it?

3.     Is it hard or soft?

4.     Is it stiff or does it bend easily?

5.     Can light pass through it?

6.     Can you see through it?

7.     Try to pull it apart.  Is it strong?  Does it break or tear easily?

8.     Would it be better to make this object out of wood, glass, or metal?  Why or why not?

 

 

 

 

  1. OBJECT 1:__________________________________________________
  2. COLOR
  3. HARDNESS
  4. FLEXIBILITY
  5. TRANSPARENCY
  6. CLARITY
  7. STRENGTH
  8. __________________________________________________________________________________________________________________________________________

NAME:____________________________DATE:_____________

 

 

 

ACTIVITY – THEY’RE EVERYWHERE!

 

 

 

 

1.   OBJECT 2:__________________________________________________

2.   COLOR

3.   HARDNESS

4.   FLEXIBILITY

5.   TRANSPARENCY

6.   CLARITY

7.   STRENGTH

8.      _____________________________________________________________________

            _____________________________________________________________________

 

 

 

1.   OBJECT 3:__________________________________________________

2.   COLOR

3.   HARDNESS

4.   FLEXIBILITY

5.   TRANSPARENCY

6.   CLARITY

7.   STRENGTH

8.      _____________________________________________________________________

            _____________________________________________________________________

 

 

NAME:____________________________DATE:_____________

 

 

 

ACTIVITY – THEY’RE EVERYWHERE!

 

 

 

 

1.   OBJECT 4:__________________________________________________

2.   COLOR

3.   HARDNESS

4.   FLEXIBILITY

5.   TRANSPARENCY

6.   CLARITY

7.   STRENGTH

8.      _____________________________________________________________________

            _____________________________________________________________________

 

 

 

 

1.   OBJECT 5:__________________________________________________

2.   COLOR

3.   HARDNESS

4.   FLEXIBILITY

5.   TRANSPARENCY

6.   CLARITY

7.   STRENGTH

8.      _____________________________________________________________________

            _____________________________________________________________________

 

ACTIVITY – THEY’RE IN MY HOUSE!

 

 

 

OBJECTIVE:

      Demonstrate to the student that polymers are found in products we use daily at home.

 

 

PURPOSE:

      After examining the labels on various products found in the home, the student will make a list of specific polymers that are ingredients found in common household items.  Although each student should do this assignment independently, one student from each work group can report out results to the class.

 

 

 

SUGGESTED VOCABULARY:

natural polymer

polypropylene

protein

polyethylene terephthalate(PET)

keratin

nylon

cellulose

Dacron®

wool

Formica®

silk

Kevlar®

synthetic polymer

Lexan®

plastics

Teflon®

polyethylene (LDPE)

Saran®

polyethylene (HDPE)

Styrofoam®

polyvinyl chloride (PVC)

 

polystyrene

 

 

 

OUTCOME:

            After the worksheet is completed, students or the group spokesperson will share results with the class.  Write the different items containing the specific polymers on the board.  The extension of this activity is to research the properties of the identified polymers either in the library or on the Internet to determine each polymer’s possible role in the individual items.

NAME:____________________________DATE:_____________

 

 

 

ACTIVITY – THEY’RE IN MY HOUSE!

 

DIRECTIONS:

Read the list of ingredients on a variety of products found in your home.  Consider cosmetics, foods, personal hygiene items, cleaning products, craft supplies, and home repair products.  List five products found in your home that contain a polymer.  Record the brand name of the item and the specific polymer as listed on the label in the table below.

 

PRODUCT

POLYMER LISTED AS AN INGREDIENT

_________________

__________________________________

_________________

__________________________________

_________________

__________________________________

_________________

__________________________________

_________________

__________________________________

 

 

 

Resin Identification Code

 

The Society of the Plastics Industry, Inc. (SPI) introduced its resin identification coding system in 1988 at the urging of recyclers around the country.  A growing number of communities were implementing recycling programs in an effort to decrease the volume of waste subject to rising tipping gees at landfills.  In some cases, these programs were driven by state-level recycling mandates.  The SPI code was developed to meet recyclers’ needs while providing manufacturers a consistent, uniform system that could apply nationwide.  Because municipal recycling programs traditionally have targeted packaging-primarily containers-the SPI coding system offered a means of identifying the resin content of bottles and containers commonly found in the residential waste stream.  Recycling firms have varying standards for the plastics they accept.  Some firms may require that the plastics be sorted by type and separated from other recyclables; some may specify that mixed plastics are acceptable if they are separated from other recyclables; while others may accept all material mixed together.  Not all types of plastics are generally recycled, and recycling facilities may not be available in some areas.

 

Plastic Resin Identification Codes

 

 

 

 

 

 

 


1--PETE--Polyethylene Terephthalate (PET)

 

2--HDPE--High Density Polyethylene

 

3--V--Polyvinyl Chloride (PVC or Vinyl)

 

 

4--LDPE--Low Density Polyethylene

 

 

5--PP--Polypropylene

 

 

6--PS--Polystyrene

 

Classification of Plastic Container

 

What do the students already know?  What will happen if…?  This part of the learning cycle actively involves the student with his or her peers with minimal teacher input.

 

Previous Week:

 

Students bring to class plastic containers with resin identification codes embossed on them.

 

You will notice that in the cases of codes #1 and #3 we refer to the resins as PET and PVC, respectively.  However, the actual codes on the containers are PETE and V.  These resins are correctly referred to in both ways.

 

It might be a good idea to award bonus points for samples brought to school so that each class has a wide variety of containers to study.  The containers are collected in a large box in the classroom.  Before the first class period on the study of plastics, the teacher must remove the embossed code on the bottom of the containers.  Just cut down the side of the container and remove it.  It is okay to partially destroy the container!  It is not necessary to save the codes nor to identify which container was coded with a particular number.

 

Student groups may be given pieces of containers for this activity.  They do not need the whole container.  It works well to have plastic bags of containers ready for each group in the class.

 


Introduce the topic of plastics by asking you students what comes into their minds when the word “plastic” is heard.  At some point in the discussion, the resin identification codes will be mentioned.  Ask your students what they think the numbers mean.  Finally, place an overhead transparency of “Plastic Resin Identification Codes” on the overhead projector (using the handout included in Classroom Materials below to make a transparency) and tell them the names for the letter abbreviations.  At this point it is not expected that students will know what is meant by the long chemical names but the introduction is important.

 

Place students into cooperative groups.  Give each group a felt tip marker, a bag of plastic containers with the plastic code removed, and the sheet Classification of Plastic Containers (see Classroom Materials below).  Challenge the groups of students to put the containers in their appropriate groupings (1-6).  These are: (1) PET, (2) HDPE, (3) PVC, (4) LDPE, (5) PP, (6) PS.

 

Sharing their ideas with others in their group and recording their thoughts is appropriate.  A student recorder should be assigned to each group.  Toward the end of the class period, one representative will share with the class their classifications of the containers and how the group arrived at their decisions.  A lively discussion may occur because the students don’t have mush information about the categories.  Keep each group’s categories of plastics in a separate place or in a bag marked for that group.  These will be used later.  A marker should be used to identify each container with the plastic number that they assigned.

Classification of Plastic Containers

 

Group Members:

 

 

 

 

 

 

 

 

 

 

 


Group Recorder:

 

 

 

 


Place each container in a specific resin code category.  There are SIX categories.  Use the physical properties to classify the containers.  Using your sense, examine each container for texture, gloss or shine, color, flexibility, transparency, odor, etc.  Remember that all six categories may not be represented by the containers you brought to school for this exercise.  Use a marker to place the number of the code on each container once the group has made its final decisions.

 

Resin Code                             Container Descriptions                     Physical Properties

 

      1-PET

 

      2-HDPE

 

      3-PVC

 

      4-LDPE

 

      5-PP

 

      6-PS

 

 

Pick a spokesperson to describe your choices for the class discussion.

 

Plastics Analysis Lab

 

1.     Before conducting this lab, students should be familiar with the concept of density.

 

2.     If students are not familiar with flow charts. We suggest that you try having them read the chart and discuss its meaning before the lab.  Have students tell which plastic floats in alcohol and oil.  Will this same plastic float in water?  Which plastic has a green flame with the copper wire test?  Will PS soften in acetone?

 

3.     The four test areas must be set up before the class starts.  Be sure to keep the flammable liquids and the hot plate in separate locations for safety reasons.  Also, make sure students wear safety glasses and avoid breathing in fumes during the experiment.

 

4.     If you do not want your students to have open flames in the room to do the copper wire test, have your students bring the resin to you to demonstrate this test for them.  Using insulated copper wire by peeling off the end of the insulation also works well for this test.

 

5.     Each group of students needs samples of the six recycled resins to identify.  Each group should have about 10 pellets of each type.

 

6.     Acetone is the active ingredient in some fingernail polish removers so your drugstore is a good source for this chemical.  Please read the label of the fingernail polish remover to make sure that the primary active ingredient is acetone.  If you use fingernail polish remover instead of acetone, students must leave the plastic sample in the liquid for a longer period of time in order to detect any softening of the plastic.  Please check the timing of this test before students do the lab.  A special container must be provided for the used resins since acetone on the pellet may be a fire hazard until the acetone evaporates.

 

7.     Isopropyl rubbing alcohol is also available from the drugstore, but make sure it is 70 percent to 90 percent, since the density is not one gram/mL.  When preparing the materials listed on page 27, 60 grams of isopropyl rubbing alcohol is equal to 65 mL for the alcohol solution.

 

8.     Mazola® corn oil has the correct density to separate #4 and #5 resins so do not substitute another kind of oil.