Synthetic resins and their raw materials / A survey of the types and uses of synthetic resins, the organization of the industry, and the trade in resins and raw materials, with particular references to factors essential to tariff consideration. Under the general provisions of section 332, title III, part II, Tariff act of 1930.

by United States Tariff Commission

The physical properties of a resin and its uses.

A more expensive resin will be used in preference to a cheaper one, only if the higher cost is more than offset by some physical property, such as color, which makes it more desirable in a particular use. The most common molding resin at present is the tar-acid type, but it is available only in the darker colors and therefore has been at a disadvantage, where a light color is desired, in competition with cellulose nitrate (celluloid) and cellulose acetate plastics or with urea and cast phenolic resins. In recent years the production of cellulose acetate molding compounds and of urea resins has increased rapidly, largely under this stimulus. The desire for color also promises well for the future of the acrylate and polystyrene resins which are produced in water-clear grades or colored with dyes or pigments.

Table 17.—Synthetic resins and other plastics: Properties that affect appearance

Type	Machining qualities	Clarity	Color possibilities	Burning rate	Effect of age	Effect of sunlight	Refractive index No1
Synthetic resins:
Tar-acid—Formaldehyde:
Molded, wood flour filler.	Fair to good.	Opaque	Limited	Very low	None	Light shades discolor
Molded, mineral filler.	do	do	do	Nil	do	do
Molded, fabric filler.	do	do	do	Approximately nil	do	do
Laminated, paper base.	Fair to excellent.	do	do	Very low	Improves mechanical and electrical properties.	Lowers surface resistance.
Laminated, fabric base.	do	do	do	do	do	do
Laminated, asbestos cloth base.	do	do	do	Approximately nil	do
Cast	Excellent	Transparent, translucent, opaque.	Unlimited	Very low	Hardens slightly	Colors may fade	1.5-1.7
Tar-acid—Furfural:
Wood flour filler.	Fair to good	Opaque	Limited	do	do	Light shades discolor
Mineral filler.	do	do	do	Nil	do	do
Fabric filler.	do	do	do	do	do	do
Urea—Formaldehyde.	Fair	Translucent, opaque	Unlimited pastel shades	Very low	do	None	1.54-1.6
Vinyl, unfilled.	Good	Transparent, translucent, opaque	Unlimited pastels to black	Nil	Strength unaffected	Darkens	1.53
Vinyl, filled.	Excellent (organic filler).	do	do	Approximately nil	None	Discolors
Acrylate	Very good	Transparent (95% light transmission).	Unlimited	Slow	do	None	1.49
Polystyrene	Poor to good	Transparent, translucent, opaque.	do	do	do	Yellows	1.67
Other plastics:
Shellac compound.	do	Opaque	Limited, pastels excluded	High (wood filler)		None
Cold molded:
Nonrefractory.	Poor	do	Dark colors only	Nil
Refractory.	do	do	Gray	do
Rubber compounds:
Chlorinated rubber.		Translucent, opaque	Unlimited	do	Slight embrittlement	Darkens	1.56
Modified isomerized rubber.	Good	Transparent	do	Slow	None	Slight surface crazing
Hard rubber.	Fair	Opaque	Limited	Medium	do	Discolors surface, resistivity decrease.
Casein	Good	Translucent, opaque	Unlimited	Very low	Hardens slightly	Colors may fade
Cellulose compounds:
Ethyl cellulose	do	Transparent, translucent, opaque	do	Slow	Slight	Slight	1.47
Cellulose acetate sheet	do	do	do	do	do	do	1.49-1.50
Cellulose acetate molding	do	do	do	do	do	do	1.47-1.50
Cellulose nitrate	do	do	do	Very high	Slight hardening	Discolors and becomes brittle	1.50

¹ Specified refractive degree.

Note.—The values for the properties in this table are based upon maximum and minimum figures submitted to Modern Plastics by a number of manufacturers of each type of material. Differences in test procedures and sizes of test specimens may lead to erroneous conclusions in some cases if direct comparisons are attempted. Special grades of materials are often available which excel in one particular property.

Source: Modern Plastics, vol. 15, no. 2, opp. p. 120. October 1937.

Table 18.—Synthetic resins and other plastics: Molding properties

Type.	General molding qualities	Compression molding temperature	Compression molding pressure	Injection molding temperature	Injection molding pressure	Compression ratio	Mold shrinkage	Effect on metal inserts
		°F.	Pounds per square inch	°F.	Pounds per square inch		Inches per inch
Synthetic resins:
Tar-acid—Formaldehyde:
Molded, wood flour filler	Excellent	280-360	1,600-4,500	275-375	2,000-10,000	2.5-3.0	0.006-0.010	Inert.
Molded, mineral filler	Excellent to fair	270-350	1,600-6,000	275-350	2,000-15,000	2.2-7.1	.002-.006	Do.
Molded, fabric filler	Good to fair	270-330	3,000-8,000			2.5-11.0	.003-.007	Do.
Laminated, paper base		250-365	1,000-3,000			1.5-3.0		Do.
Laminated, fabric base		250-365	1,000-3,000			1.5-3.0		Do.
Laminated, asbestos cloth base		250-325	1,000-3,000					Do.
Cast								Do.
Tar-acid—Furfural:
Wood flour filler	Excellent	330-400	1,000-3,000	250-290	300-5,000	2.5-3.0	.005-.009	Do.
Mineral filler	do	330-360	1,000-3,000	250-290	300-5,000	2.5-6.0	.002-.006	Do.
Fabric filler	Good to fair	300-360	1,000-3,000	250-290	300-50,000	4.0-15.0	.0025-.006	Do.
Urea—Formaldehyde (alpha cellulose filler)	Excellent	290-325	1,500-6,000			3.0	.007-.011	Do.
Vinyl, unfilled	Good	240-275	1,500-2,000			2.0	.001	Not used.
Vinyl, filled	Excellent	250-300	2,000-2,500			1.5-3.5	.000	Inert.
Acrylate	do	285-315	1,500-5,000	325-475	3,000-30,000	2.0	.002-.003
Polystyrene	Good	280-325	300-2,000	300-375	3,000-30,000	2.5	.002-.0025
Other plastics:
Shellac compound	do	240	1,000-1,200				.002	Do.
Cold molded:
Nonrefractory	Fair		4,000-12,000			2.5	.000-.022	Do.
Refractory	do		4,000-12,000			3.5	.000	Do.
Rubber compounds:
Chlorinated rubber	do	200-225	2,000-5,000			2.0-3.0
Modified isomerized rubber	Good	260-300	1,200-4,000			3.0	.000	Do.
Hard rubber	Fair	285-350	1,200-1,800	180-220	2,000-5,000	4.0-6.0
Casein	Poor	200-225	2,000-2,500
Cellulose compounds:
Ethyl cellulose	Excellent	212-300	1,000-5,000			2.2-2.9	.0003-.0007	Do.
Cellulose acetate sheet	do	210-320	500-5,000				(1)	Do.
Cellulose acetate molding	do	250-350	500-5,000	300-440	3,000-30,000	2.0-2.8	(1)	Do.
Cellulose nitrate	Good	185-250	2,000-5,000

¹ Positive and injection 0.002-0.003; semipositive 0.005-0.007; flash 0.008-0.009.

Note.—The values for the properties in this table are based upon maximum and minimum figures submitted to Modern Plastics by a number of manufacturers of each type of material. Differences in test procedures and sizes of test specimens may lead to erroneous conclusions in some cases if direct comparisons are attempted. Special grades of materials are often available which excel in one particular property.

Source: Modern Plastics, vol. 15, No. 2, opp. p. 120. October 1937.

Table [17] lists the properties which affect appearance and gives in addition to the color range, the clarity, material, the burning rate, the effect of age and sunlight, the refractive index, and the machining quality of each synthetic resin.

Table [18] lists molding properties of synthetic resins. Of special interest are the possibilities of using a resin in injection molding. The thermoplastic resins and plastics (see softening point in table [20]) are generally preferred to the thermosetting materials for injection molding because they permit the reuse of material otherwise wasted.

Table [19] lists the strength properties of the synthetic resins; table [20] the heat properties; table [21] the electrical properties; and table [22] the resistance to acids, alkalies, and solvents. All of these qualities are important in some uses and each quality may be paramount in a few. Each material has its limitations and its special advantages and the consuming industry must choose the one best suited to its purposes. The tie-up between specific properties and particular uses is exemplified by vinyl resins, which because of their great elasticity at low temperatures, are used in safety glass, and by the polystyrene resins, which because of their electrical properties at high frequencies, are used in laminated electrical parts. As production of the various resins increases new uses will probably be found for most of them.

Table 19.—Synthetic resins and other plastics: Strength properties

Type	Tensile strength	Elongation	Modulus of elasticity	Compressive strength	Flexural strength	Impact strength1 (foot pounds)	Hardness2
	Pounds per square inch	Percent	Pounds per square inch × 10³	Pounds per square inch	Pounds per square inch		Brinell No
Synthetic resins:
Tar-acid—Formaldehyde:
Molded, wood flour filler	6,000-11,000		10-15	16,000-36,000	8,000-15,000	0.10-0.28; I, N	30-45
Molded, mineral filler	5,000-10,000		10-45	18,000-36,000	8,000-20,000	0.11-0.36; I, N
Molded, fabric filler	6,500-8,000		7-12	20,000-32,000	10,000-13,000	0.4-2.4; I, N
Laminated, paper base	6,000-13,000		5-20	20,060-40,000	13,000-20,000	0.4-1.2; I, N	24-40
Laminated, fabric base	8,000-12,000		5-15	20,000-44,000	13,000-20,000	0.8-5.2; I, N	30-45
Laminated, asbestos cloth base	9,000			18,000-40,000	17,000
Cast	5,000-12,000		5-15	15,000-30,000		0.1-1.5; I, N	30-45
Tar-acid—Furfural:
Wood flour filler	5,000-12,000		10-25	28,000-36,000	10,000-16,000	0.08-0.52; C, N	335-40
Mineral filler	4,000-12,000		10-45	24,000-36,000	8,000-14,000	0.08-0.48; C, N	344-46
Fabric filler	5,000-10,000		7-12	26,000-30,000	10,000-16,000	1.6-3.1; C, N	330-35
Urea—Formaldehyde	8,000-13,000		16	24,000-35,000	13,000-15,000	0.7-1.5; C, U	448-54
Vinyl, unfilled	8,000-10,000		3.5-4.1		10,000-13,000	0.3-0.6; I, N	15-25
Vinyl, filled	6,000-12,000		3.5-8.5			0.1-0.7; I, N	15-25
Acrylate	7,000-9,000	1.0	6	8,000	15,000-17,000	0.25-0.5; C, N	418-20
Polystyrene	5,500-7,500	1.0	4.6-5.1	13,000-13,500	6,500-8,000	0.16-0.25; I, N	20-30
Other plastics:
Shellac compound	900-2,000
Cold molded				6,000-15,000	5,300-7,500	0.4; C
Nonrefractory	}			16,000	6,000	0.4; C
Refractory
Rubber compounds:
Chlorinated rubber						3.0+; C, U
Modified isomerized rubber	4,300	0.013	4.7	8,500-11,000	7,000-9,000	2.6-6.2; I, N	585-90
Hard rubber	4,000-10,000	8-15	5.3	8,000-12,000		0.5; I	31
Casein	7,600		5.1-5.7			1.0; I	23
Cellulose compounds:
Ethyl cellulose	2,000-7,000		2.8			1-4; I, N (per in. sq.)
Cellulose acetate sheet	6,000-11,000	20-55	1-3	4,000-16,000		2-7; C, N (per in. sq.)	66-11
Cellulose acetate molding	3,500-10,000	10-48	2-4	11,000-16,000	5,200-8,800	3-12; C, N (per in. sq.)	66-7.5
Cellulose nitrate	5,000-10,000	10-40	2-4			3-12; C, N (per in. sq.)	68-11

¹ ASTM D256-34T. C = Charpy; I = izod; N = notched; U = unnotched.

² 2.5 mm ball; 25 kg. load unless otherwise noted.

³ 50 kg. load.

⁴ 10 mm. ball; 500 kg. load.

⁵ Shore.

⁶ 10 kg. load.

Note.—The values for the properties in this table are based upon maximum and minimum figures submitted to Modern Plastics by a number of manufacturers of each type of material. Differences in test procedures and sizes of test specimens may lead to erroneous conclusions in some cases if direct comparisons are attempted. Special grades of materials are often available which excel in one particular property.

Source: Modern Plastics, vol. 15, No. 2, opp. p. 120; October 1937.

Table 20.—Synthetic resins and other plastics: Heat properties

Type	Thermal conductivity	Specific heat	Thermal expansion	Resistance to continuous heat	Softening point	Distortion under heat	Tendency to cold flow
	10⁻⁴ calories per second per square centimeter per 1°C. per centimeter	Calories per °C. per gram	10⁻⁶ per °C.	°F.	°F.	°F.
Synthetic resins:
Tar-acid—Formaldehyde:
Molded, wood flour filler	4-12.2	0.35-0.36	3.7-7.5	350	None	240-285	None.
Molded, mineral filler	8-20	0.25-0.35	2.5-4	450	do.		Do.
Molded, fabric filler	3-5	0.30-0.35	2-6	250-350	do.		Do.
Laminated, paper base	5-8	0.3 -0.4	2	212-300	do.	320	Do.
Laminated, fabric base	5-8	0.3 -0.4	3	212-350	do.		Do.
Laminated, asbestos cloth base			2	400-500	do.		Do.
Cast	3-5	0.3-0.4	2.8	160
Tar-acid—Furfural:
Wood flour filler	3.5-5	0.3-0.4	3	280-400	Chars 450	268-288	Do.
Mineral filler	10-20	0.3-0.4	2	350-500	Chars 550	277-297	Do.
Fabric filler	5-8	0.3-0.4	4.5	280-350	Chars 400		Do.
Urea—Formaldehyde	7.13		1.5	160	None	260	Do.
Vinyl, unfilled	4	0.244	6.9		130-160	140-150	Slight.
Vinyl, filled	Varies	Varies	Varies		130-160	140-158	Do.
Acrylate	4.3-6.8	0.45	8.5		170-235	158	Do.
Styrol	1.9	0.324	10.2		110-200	185	Do.
Other plastics:
Shellac compound				150-190	150		Do.
Cold molded:
Nonrefractory				500
Refractory				1,300
Rubber compounds:
Chlorinated rubber					175-230	140	Do.
Modified isomerized rubber	2.6-2.9		7-8		165-220	167-221	Do.
Hard rubber	3.2	0.33	8.0		150-190		Do.
Casein			8			200
Cellulose compounds:
Ethyl cellulose						210-266
Cellulose acetate sheet	5.4-8.7	0.3-0.4	14-16	140-180	140-230	122-212	Do.
Cellulose acetate molding	5.4-8.7	0.3-0.45	14-16	140-180	145-260	122-212	Do.
Cellulose nitrate	3.1-5.1	0.34-0.38	12-16	ca. 140	160-195

Note.—The values for the properties in this table are based upon maximum and minimum figures submitted to Modern Plastics by a number of manufacturers of each type of material. Differences in test procedures and sizes of test specimens may lead to erroneous conclusions in some cases if direct comparisons are attempted. Special grades of material are often available which excel in one particular property.

Source: Modern Plastics, vol. 15, No. 2, opp. p. 120. October 1937.

Table 21.—Synthetic resins and other plastics: Electrical properties

Type	Volume resistivity (50 percent relative humidity) (ohm = cms)	Breakdown voltage, 60 cycles (volts per mil (instantaneous))	Dielectric constant			Power factor
			60 cycles	10³ cycles	10⁶ cycles	60 cycles	10³ cycles	10⁶ cycles
Synthetic resins:
Tar-acid—Formaldehyde:
Molded, wood flour filler	10¹⁰-10¹²	300-500	5-12	4-8	4.5-8	0.04-0.30	0.04-0.15	0.035-0.1.
Molded, mineral filler	10⁹-10¹¹	250-400	5-20	4.5-20	4.5-20	0.10-0.30	0.10-0.15	0.005-0.1.
Molded, fabric filler	10⁹-10¹¹	300-450	5-10	4.5-6	4.5-6	0.08-0.30	0.08-0.20	0.04-0.1.
Laminated, paper base	10¹⁰-10¹³	400-1,300			4-6			0.02-0.05.
Laminated, fabric base	10¹⁰-10¹²	150-600			4.5-7			0.02-0.08.
Laminated, asbestos cloth base		90
Cast	10⁹-10¹⁴	300-450	5-10		5-7	0.025-0.20	0.005-0.08	0.01-0.045.
Tar-acid—Furfural:
Wood flour filler	10¹⁰-10¹²	400-600		4-8	6-7.5		0.04-0.15	0.035-0.1.
Mineral filler	10⁹-10¹¹	200-500		4.5-20	5-18		0.1-0.15	0.04-0.1.
Fabric filler	0.4 × 10¹¹	200-500		4.5-6	5-7.5		0.08-0.20	0.035-0.1.
Urea—Formaldehyde	(2-2.8) × 10¹³	650-720	6.6		6	0.034		0.01-0.03.
Vinyl, unfilled	10¹⁴	400-500			4		0.0143	0.0175.
Vinyl, filled	10¹¹	350-400		4.7	4		0.02-0.15	0.02-0.065.
Acrylate	10¹⁵	480	4-6		2.8	0.06-0.08		0.02.
Polystyrene	10¹⁷-10¹⁸	500-700	2.6	2.65	2.7	0.0003	0.0001	0.0001.
Other plastics:
Shellac compound		100-400
Cold molded:
Nonrefractory	1.3 × 10¹²	85	15		6	0.20		0.07.
Refractory
Rubber compounds:
Chlorinated rubber		2,300	ca. 3			0.003
Modified isomerized rubber	(5-7) × 10¹⁶		2.7	2.68		0.006		0.0016.
Hard rubber	10¹²-10¹⁵	250-900	2.8		3			0.003-0.008.
Casein		400-700			6.15-6.8			0.052.
Cellulose compounds:
Ethyl cellulose		1,500		3.72			0.011
Cellulose acetate sheet	(5-30) × 10¹²	800-2,500	5.1-7.5		4.2-5.3	0.025-0.07		0.038-0.091.
Cellulose acetate molding	(4.2-6.2) × 10¹²	800-850	5.8-6.0		4.4-4.6	0.042-0.058		0.038-0.042.
Cellulose nitrate	(2-30) × 10¹⁰	600-1,200	6.7-7.3		6.15	0.062-0.144		0.074-0.097.

Note.—The values for the properties in this table are based upon maximum and minimum figures submitted to Modern Plastics by a number of manufacturers of each type of material. Differences in test procedures and sizes of test specimens may lead to erroneous conclusions in some cases if direct comparisons are attempted. Special grades of materials are often available which excel in one particular property.

Source: Modern Plastics, vol. 15, No. 2, opp. p. 120. October 1937.

Table 22.—Synthetic resins and other plastics: Specific gravity, specific volume, and resistance to other substances

Type	Specific gravity	Specific volume	Water absorption, immersion 24 hours1	Effect of weak acids	Effect of strong acids	Effect of weak alkalies	Effect of strong alkalies	Effect of organic solvents
		Cubic inches per pound
Synthetic resins:
Tar-acid—Formaldehyde:
Molded, wood flour filler	1.34-1.52	20.7-18.2	0.2-0.6	None to slight.	Varies2	Slight to marked	Decomposes	None.3
Molded, mineral filler	1.70-2.09	16.4-13.3	0.01-0.3	do.	do.2	do.	do.	Do.3
Molded, fabric filler	1.37-1.40	20.2-19.8	1.0-1.3	do.	do.2	do.	do.	Do.3
Laminated, paper base	1.34-1.55	20.7-17.8	0.5-9.0	do.	do.2	do.	do.	Do.3
Laminated, fabric base	1.34-1.55	20.7-17.8	0.5-9.0	do.	do.2	do.	do.	Do.3
Laminated, asbestos cloth base	1.6-1.65	17.3-16.8	0.5	do.	do.2	do.	do.	Do.3
Cast	1.27-1.32	21.8-20.0	0.01-0.5	do.		do.	do.	Do.
Tar-acid—Furfural:
Wood flour filler	1.3-1.4	21.3-19.8	0.2-0.6	do.	do.2	do.	do.	Do.
Mineral filler	1.6-2.0	17.3-13.9	0.01-0.15	do.	do.2	do.	do.	Do.
Fabric filler	1.3-1.4	21.3-19.8	0.8-1.4	do.	do.2	do.	do.	Do.
Urea—Formaldehyde	1.48-1.50	18.7-16.5	1-2	do.	Decomposed or surface attacked.	do.	do.	Do.
Vinyl, unfilled	1.34-1.36	20.7-20.4	0.05-0.15	Resistant	Resistant	Resistant	Resistant	(4).
Vinyl, filled	1.35-2.5	20.5-11.1	0.2-4.0	Dependent on filler.	Dependent on filler.	Dependent on filler.	Dependent on filler.	(4).
Acrylate	1.18	23.3	0.3	None	Oxidizing acids attack surface.	None	Slight	(5).
Polystyrene	1.05-1.07	26.3-25.8	0	do.	None	do.	None	Widely soluble.
Other plastics:
Shellac compound	1.1-2.7	25.2-10.3		Deteriorates	Deteriorates	Deteriorates	Deteriorates	Attacked by some.
Cold molded:
Nonrefractory	1.98-2.0	14.0-13.9	1.5	Slight	Decomposes	Decomposes	Decomposes	Do.
Refractory	2.2	12.6	0.5-15	Decomposes	do.	None	None	None.
Rubber compounds:
Chlorinated rubber	1.5	18.5	0.1-0.3	Resistant	Resistant	Resistant	Resistant	Soluble in aromatic hydrocarbons.
Modified isomerized rubber	1.06	26.1	0.02	do.	do.	do.	do.	Attacked by some.
Hard rubber	1.12-1.8	24.7-15.4	0.02	do.	Attacked by oxidizing acids.	do.	do.	Do.
Casein	1.35	20.5	3-7	do.	Decomposes	Softens	Decomposes	Resistant.
Cellulose compounds:
Ethyl cellulose	1.14	24.3	61.25	Slight	Decomposes	None	None.	Widely soluble.
Cellulose acetate sheet	1.27-1.37	21.8-20.2	1.5-3.0	do	do	Slight	Decomposes	(7).
Cellulose acetate molding	1.27-1.63	21.8-17.0	1.4-2.8	do	do	do	do	(7).
Cellulose nitrate	1.35-1.60	20.5-17.3	1.0-3.0	do	do	do	do	(7).

¹ ASTM D48-33.

² Decomposed by oxidizing acids; reducing and organic acids no effect.

³ On bleed-proof materials.

⁴ Resists alcohols, aliphatic hydrocarbons, and oils. Soluble in ketones and esters; swells in aromatic hydrocarbons.

⁵ Soluble in ketones, esters, and aromatic hydrocarbons.

⁶ 48 hours.

⁷ Soluble in ketones and esters; softened by alcohols; little affected by hydrocarbons.

Note.—The values for the properties in this table are based upon maximum and minimum figures submitted to Modern Plastics by a number of manufacturers of each type of material. Differences in test procedure and sizes of test specimens may lead to erroneous conclusions in some cases if direct comparisons are attempted. Special grades of materials are often available which excel in one particular property.

Source: Modern Plastics, vol. 15, No. 2, opp. p. 120. October 1937.